"Law's Empire and the Final Frontier: Legalizing the Future in the Early Corpus Juris Spatialis," 108 Yale L.J. 1737 (1999) (note)

"Law's Empire and the Final Frontier: Legalizing the Future in the Early Corpus Juris Spatialis," 108 *Yale L.J.* 1737 (1999) (note)

Barton Beebe, Note, Law's Empire and the Final Frontier: Legalizing the Future in the Early Corpus Juris Spatialis, 108 Yale L.J. 1737 (1999)

The Yale Law Journal [Vol. 108: 1737 " the legal aspects of rainmaking?" 9 What are the career prospects for the " space lawyer," 10 and to what extent should she prepare for " relativity problems?" 11 As improbable as they may sound to modern readers, such questions were highly fashionable in legal thought and law school classrooms during the " golden age" 12 of space law. Roughly contemporaneous with the " Space Age" itself, this period began with the Sputnik and Explorer launches of the late 1950s, reached its height with the " space boom" of the mid-1960s, and ended with the latter stages of the Apollo program and the " space bust" of the mid-1970s. 13 During this period, an international Corpus Juris Spatialis, or body of space law, quickly developed. Despite the tensions of the Cold War and the spacepowers' difficulties in predicting their own interests in outer space, Apollo-era space law managed several substantive achievements: the 1959 Report of the Ad Hoc Committee on the Peaceful Uses of Outer Space, 14 the 1963 Declaration of Legal Principles Governing the Activities of States in the Exploration and Use of Outer Space, 15 and the near-legendary Outer Space Treaty of 1967. 16 These advances were followed by a period of consolidation, 17 in the Rescue The Yale Law Journal [Vol. 108: 1737 momentum of the movement " [b]efore legal speculation reaches escape velocity." 28 Even then they were apparently too late, and it was left to Nicholas Katzenbach to acknowledge the full scope of lawyerly hubris in the pages of the June 1958 Bulletin of the Atomic Scientists: " We have already explored Space, the Moon, Mars, and other bodies and are fast reducing the whole universe to a purely legal problem. . . . By comparison the scientists are barely off the ground." 29 The " extensive and chaotic body of literature" on the law of outer space, which broke in " the midtwentieth century . . . the monopoly of science fiction writers," 30 was indeed controversial. Its critics seem to have enjoyed ridiculing it, and in ever more hyperbolic terms. Thus, space law's Cold War context produced " the political bedlam of space law." 31 Its naïveté before the language of realpolitik risked " suicide by semantics." 32 Its tendency towards prescription was symptomatic of a " Mosaic Syndrome" 33 and threatened to unleash the " psychoses of a gold rush." 34 To make matters worse, a young reviewer writing in the pages of the Harvard Law Review anxiously denounced the movement's most revered text, Myres McDougal, Harold Lasswell, and Ivan Vlasic's Law and Public Order in Space. 35 The treatise's " excessive conceptualism" 36 and " heavy 28. Id. at 407. 29. Nicholas Katzenbach, Law and Lawyers in Space, 14 BULL. ATOM. SCI. 220 (1958); see also AMERICAN layers of rules and generalities of dubious value" 37 resulted in a " handbook of analogies" 38 that was " high-sounding, but on examination almost meaningless," 39 " even casuistic." 40 The book, in Richard Posner's view, was a failure; " the tough questions for the most part get swept under the rug." 41 Nor did the magnitude of the movement escape the somewhat derisive notice of the popular media. Early space law earned for itself such dubious honors as a center column article in the Wall Street Journal, 42 an appearance in Grin & Bear It, 43 and a misprint to which the New Yorker called attention: " Every 24 hours many thousand meteorites approach the earth from outer space, but many fail to survive contact with the outer lawyers of the atmosphere." 44 It is appropriate that the early years of space law should be described with images of psychosis and escape, for Apollo-era space law was a talking cure. The disease was the rise of science and the prognosis was the death of law. In seeking to make sense of the extraordinary outpouring of legal commentary on outer space in the late 1950s and early 1960s, this Note interprets early space law as a means by which the legal profession sought to assert its continued vitality in an age of science and technocracy. Part II shows how the overriding positivism and technological spectaculars of the Space Age were perceived to threaten the prestige of legal practice and the utility of legal knowledge. The image of outer space itself-as a " legal vacuum," as the scientized, utopian future of humanity-posed a radical challenge to law's claims to universality. The result was the law's own, professional " Sputnik Crisis." Part III evaluates the legal estate's efforts to coopt what threatened it. Early space law sought to reduce outer space to the familiar rhetoric of property and sovereignty, and to develop a legal code for scientific custom in space. In assimilating to the law the very space that science identified as its own, the legal profession resisted the 1960s' orthodox image of the future as one of technological heavens and 37. Id 42. Jerrold L. Schecter, Space Lawyers Ponder Ownership of Moon, Plot Spatial Borders, WALL ST. J., Jan. 20, 1958, at 1. The front-page center column of the Wall Street Journal is, writes Louis Trager, " a spot the paper has reserved since time immemorial for stories on the offbeat, weird and just plain goofy." Louis Trager, Is S.F. Exotic or Just Goofy? Article Has Some Concerned How City Plays in Peoria, S.F. EXAMINER, Feb. 3, 1995, at B1. The Journal editorialized the next day about " interstellar legal minds" who " don't have their feet on the ground." Editorial, Moonlight and Legal Light, WALL ST. J., Jan. 21, 1958, at 10. 43. The cartoon showed an expert telling a conference of generals that " [t]here are bound to be legal squabbles about claims on the moon, gentlemen. I think the first astronaut we land there should be a lawyer." The cartoon is cited in Albert M. Kuhfeld In an infamous phrase, President Nixon called Apollo 11 the " greatest week in the history of the world since the Creation." 45 If the mythmakers at NASA were to be believed, then Nixon was not far off the mark. For a democracy capable of Hiroshima, NASA introduced the rocket launch as the new spectacle of state power and the surveillance satellite as the new symbol of state knowledge. 46 For a nation fearful of communist expansion, Tranquility Base confirmed the full reach of Manifest Destiny. For a postwar culture aspiring to make sense of its momentum in the world, the frontier epic of space exploration valorized American exceptionalism and interpreted it as foreordained by the gods. 47 46. William Atwill proposes an interesting reading of the space program along these lines: Add to this ambivalence [about the Manichean nature of technology] the very public (televised) history of the space age and you have, perhaps, the best example of Guy Debord's postmodernist " Society of the Spectacle" as well as this century's benign version of Michel Foucault's " spectacle of the scaffold" in the sense that the space program served as a public stage on which a sovereign's power and control were inscribed on the hearts and minds of the assembled though a mediated enactment upon representative individuals. . . . [T]he space program was the most effective display of power in this century, a dispersed, nearly invisible coercion of the souls of people by way of a technological display apparently benign in its application. We were thrilled at the technological possibilities of communications satellites, weather satellites, probes to distant planets, and voyages of men to the moon, but all those years of admonition to " watch the skies" hovered at the edge of our consciousness to remind us that more sinister payloads could also be delivered The Final Frontier 1743 an image of the nation's technological future. In Houston, Cape Kennedy, Washington, and now on the Moon, the promise of the Great Society would be fulfilled by America's " new priesthood" 49 of scientists and technicians, a caste of " saviors and miracle workers" 50 who could command enormous instrumental power and symbolic capital 51 with an aura of total competence. Of course, that " Whitey's on the moon" 52 meant different things to different people. For many of its critics, the space program represented the birth of a new, technocratic order in society. As the defining moment in the history of the American Rocket State, 53 Apollo 11 could be understood as the prodigy not of miracle workers, but of specialists without spirit. At NASA and elsewhere, the nation's new class of " technologues" 54 promised neutral technical means towards self-evident political ends and fashioned a legitimating ideology out of the " end of ideology" itself. In doing so, they made the dream of escape into space all the more appealing as they created on Earth the material conditions for the " technocratic consciousness" 55 of " one-dimensional man." 56 No wonder American liberal intellectuals responded to the space program's " behemoth piece of American America and in the ultimate beneficence of advanced industrialization. This final avatar of the technological sublime is a literal escape from the threatened life-world." 59 The nation's lawyers, however, did not have that luxury. For them, or at least for those who called themselves " space lawyers," the Space Age threatened the art of legal practice and the scope of legal knowledge. Indeed, for some, it meant the death of law. Section A surveys the rise of the American Rocket State as a technocratic ideology. After a review of the Sputnik Crisis, the Section considers the American space program's evolving mandate as a model for national progress. It then assesses contemporary criticisms of technocracy and space exploration. Section B describes how the American legal profession responded to Sputnik and to the sudden clamor for scientific supremacy that followed in its wake. Section C speculates on why the legal profession reacted as nervously as it did to the onset of the Space Age. As in the scientific future it predicted, so in the scientific frontier it opened up and explored, the Space Age promoted a world in which legal knowledge would become obsolete. The origins of the American Rocket State have been traced to wartime Germany. 60 The more conventional account begins on October 4, 1957, when the Soviet Union successfully orbited Sputnik I, and the American " Sputnik Crisis" began. 61 Within a month, the Soviets orbited Sputnik II, which carried the dog Laika, earning the satellite the popular name " Muttnik." 62 ability to deliver nuclear warheads to any spot on the globe. 63 On December 6, America attempted its first, hurried response. In a now famous image, the U.S. Navy's Vanguard TV-3 rocket, the American " Kaputnik," exploded on the launch pad while the world media watched. This series of events was a " propaganda triumph" 64 for the Soviet Union and probably its finest hour on the world stage. For the United States, it was declared an unthinkable reversal. 65 The Soviets had refuted in an instant what America's postwar " victory culture" 66 had taken for granted: the nation's overwhelming technological superiority, the preeminence of its democratic institutions, and the unrivaled ingenuity of American capitalism. Or so said congressional Democrats, 67 and as President Eisenhower recovered from his stroke of November 1957, his popularity fell as much as twenty-five points from its postelection high. 68 The immediate effect of the Sputnik Crisis in America was a call for total mobilization, for " blood, sweat and tears," 69 in pursuit of scientific and technological superiority. This call extended to the nation's educational system, to its industrial base, to its commodity culture, and, of course, to its methods of governance. Ever prudent, Eisenhower refused to be carried away by the panic. In his 1958 State of the Union Address, he declared that the Soviet Union had begun to wage " total cold war," 70 but proposed only modest reforms. It was left to the Kennedy and Johnson Administrations, to the New Frontier and the Great Society, to wage total cold war in return. free, is at stake. Little Lemon [sic], the shaggiest dog, the first real space dog, may be more fortunate than those who sent him aloft, luckier than those in other lands who have to read his portent and take measures accordingly." ). 63. One result was that by the mid-1960s, science became " the major Establishment in the American political system," 71 and the technocratic rhetoric of systems theory, 72 cybernetics, 73 and synoptic decisionmaking 74 became the new language of power. As Hans Morgenthau wrote in 1964, " [i]n the eyes both of the political authorities and the public at large, the scientific elites appear as the guardians of the arcana imperii, the secret remedies for public ills." 75 It was one such guardian, Secretary of Defense Robert S. McNamara, who probably expressed the new technocratic ethos best in The Essence of Security: " [T]he real threat to democracy comes not from overmanagement, but from undermanagement. To undermanage reality is not to keep it free. It is simply to let some force other than reason shape reality. . . . [I]f it is not reason that rules man, then man falls short of his potential." 76 Truly, it was, for some, an Apollonian age-one that began and would end in war. The rise of NASA both contributed to and reflected the more general rise of technocracy in American society. In March 1958, NASA was established as a civilian agency charged with defending American prestige in the eyes of the world. With its famed " aura of competence," 77 the space program soon came to represent big, expensive government that worked. NASA chief James E. Webb called his agency a " prototype for tomorrow," the " pattern needed by this nation" in which progress obtained through 71. Don K. Price, The Scientific Establishment, in THE POLITICS OF SCIENCE, supra note 50, at 70, 71. Meg Greenfield offers her own account of the rise of science: In the beginning, a current saying in Washington goes, were the lawyers; next came the economists; and then came the businessmen. Now it is the scientists' turn. This new breed, or more precisely, these new hybrids, who began their more or less reluctant ascent to power during the Second World War, are now so thoroughly enmeshed and infiltrated into every level of government that no one seems capable of stating with any precision just what their function is. Greenfield, supra note 50, at 124. Later in the article, Greenfield makes explicit reference to Sputnik: " What has happened since Sputnik rattled the china in 1957 has been an elevation of scientists, who were for the most part already there, to posts of new responsibility with access to the top. " The Final Frontier 1747 " 'adaptive, problem-solving, temporary systems of diverse specialists, linked together by coordinating executives in organic flux.'" 78 As Webb's exotic rhetoric suggests, and as Walter McDougall has persuasively argued, NASA helped to convert American politics over to the " technocratic temptation" 79 by serving as a " model for the application of the technocratic method to civilian goals." 80 Despite the protestations of many in the American scientific community, NASA was also popularized as the archetype of state-sponsored " command technology" and as proof, however tenuous, of the material, intellectual, and spiritual advantages that would flow from it. 81 Though the American space program became a cultural icon in the 1960s, the technocratic worldview that it came to symbolize was not without its detractors. For Hannah Arendt, space exploration abetted modernity's " rebellion against human existence." 82 The narrator of Norman Mailer's Of a Fire on the Moon offered a subtle, though hardly reassuring, variation on this theme. For him, space exploration held out the hope of humanistic rebellion against modernity: " [T]echnology had penetrated the modern mind to such a depth that voyages in space might have become the last way to discover the metaphysical pits of that world of technique which choked the pores of modern consciousness." 83 When the likes of Arendt or Mailer criticized the space program in these terms, they did so as part of the Space Age's wide-ranging and oftentimes best-selling literature on the specter of technocracy in the industrialized world. 84 This literature took a 78. JAMES E. WEBB, SPACE AGE MANAGEMENT: THE LARGE-SCALE APPROACH 29 (1969) (quoting Warren G. Bennis, New Patterns of Leadership for Tomorrow's Organizations, TECH. REV., Apr. 1968, at 37). 79. MCDOUGALL, supra note 13, at 306 (" For the commitment to go to the moon did more than accelerate existing trends in space. It served as a bridge over which technocratic methods passed from the military to the civilian realm in the United States, to political problems at home as well as abroad. Sharp disagreements arose over the goals that government ought to pursue, but by 1964 little dissent remained over the methods. Under the impact of total Cold War, with the space program serving as lever, Left and Right, dove and hawk succumbed to the technocratic temptation." ). 80. In its more precise incarnations, it predicted-and sometimes purported to expose-the devolution of political authority upon the bureaucratic expert and the reordering of political values according to the imperatives of scientific/technological convergence. 85 In its more ambitious incarnations, it also criticized the totalitarian spirit of the age 86 and declared the death of the subject. 87 For those who subscribed to this critique, the space program was little more than technocratic pyramidbuilding and a well-orchestrated distraction from the discontents of technological civilization. The astronaut, meanwhile, became the controversial ideal type of the technocratic Zeitgeist-a scientific superman to his many admirers, a soulless organization man, the consummate " cheerful robot," 88 to the few who begrudged him his fame. Given the degree to which the Sputnik Crisis permeated American life, it may not surprise that the American legal profession experienced its own Sputnik Crisis, one that took the form of a sudden flood of legal commentary on space exploration in seminars 89 and symposia, 90 in bar journals, both local 91 and national, 92 in law journals, 93 and in the popular media. 95 To be sure, this was a distinctively professional rather than patriotic crisis. The " rival system[]" 96 was not communism, but science. The remarks of Senator Kenneth B. Keating are representative in this regard. In a January 1958 address before the New York State Bar, Keating spoke of the " recent Buck Rogerish achievements" 97 in space exploration and the " new-found glamor of the sciences." " Technology with a capital 'T' is on every tongue. Definitely, the sciences are on the ascendancy. There is no question about that." 98 He then cautioned: " The lawyer should not resent this." 99 Resentment was nevertheless the order of the day, and for good reason. Not only did science reveal in the satellite orbits of 1957 and 1958 the rhetorical force of its achievements, but it was perceived to have done so in a profoundly lawless fashion. In one respect, the spacepowers neither sought nor expressed any opinion on the legality of their acts. Thus the " Chairman's Message" in the May 1958 issue of the American Bar Association's Section of International and Comparative Law Bulletin complained: " In 1957 the U.S.S.R. launched its sputniks into space. Later, American satellites joined in circling the earth in flights completely free from even the pretense of legal control." 100 precisely what had happened, or so it seemed to those lawyers for whom " legal vacuum" was a favored expression of self-reproach. 103 This identification of science as the antagonist, combined with the spacepowers' reticence, created the conditions for a surprisingly altruistic, cosmopolitan discussion of space law in the months following Sputnik. This altruism was tempered, however, by the legal profession's insistent rhetoric of prerogative and entitlement, of exclusive competency over " the domain of the space lawyers." 104 Alarmist statements were typical. Lawyers declared that the franchise was now imperiled, if not on Earth, then certainly in outer space: Admittedly, most of the space-law problems are still in the future. However, this is not in itself a reason why lawyers should not concern themselves with the questions that may arise or their possible solutions. If lawyers do not concern themselves with these questions, others will-and we may some day find ourselves confronted, by default, with undesirable laws or regulations or, by the same token, we may find that non-lawyers have entered the field to our disadvantage. 105 101. Eilene n.p., 8 (" outer space was a virgin space before man entered it, to which in absence of human activities the provisions of law did not apply" ); Schacter, supra note 1, at 71 (characterizing outer space as " legally . . . a no man's world" ); Simpson, supra note 91, at 356 n.5 (" At least one husband is apparently depending upon space travel to solve his marital problems. He has enthusiastically volunteered his wife as a passenger in the first rocket ship to the moon." ); Wurfel, supra note 93, at 271 (characterizing outer space as a " Pandora's box of space facts with the lid ajar" ). In this sense, the Space Age would be " a turning point in our honored profession," 106 one in which lawyers were going to be either " Eagles or Turtles." 107 Some would eventually counsel against this paranoid style. Others, such as the irrepressible William Hyman, were far less restrained: " The void in space is law. This must be filled and it must be filled immediately. The time for launching is now! Go! Go!! Go!" 108 Such enthusiasm had a predictable result. " Many scientists like to jibe their lawyer friends for what they allege is an unnecessary desire to 'get into the space act,'" wrote Philip B. Yeager in the American Bar Association Journal. 109 Yet, as far as Senator Keating was concerned, the very fate of the bar demanded immediate action: " [A]t the threshold of a new age of exploration and discovery. . . . the American lawyer . . . must lead the way. . . . We choose between greatness-and oblivion." 110 The legal profession's Sputnik Crisis soon expanded beyond mere calls for the rule of law in outer space. As American society turned to science, American lawyers began to suggest that the choice between greatness and oblivion had already been made-if not in outer space, then certainly on Earth. " The technocrat is not the new messiah," declared Arthur Selwyn Miller in the Buffalo Law Review, " and it is high-time lawyers recognized it." 111 Yet many legal commentators openly acknowledged the ascendancy of the scientific estate in the early 1960s and acceded to its privileging of technical " competence" over " customary knowledge." 112 In an act perhaps best described as " cultural cringe," 113 to borrow a term from postcolonial studies, various lawyers declared their loss of status, if not their outright " abdication" 114 of social and political authority. " The The Yale Law Journal [Vol. 108: 1737 simple fact is that law has not kept abreast of science," reported Chief Justice Warren in his 1963 address on the subject. 115 Others spoke of the lawyer's " inertia," 116 scientific illiteracy, 117 irrational devotion to an " ancient common law tradition," 118 and blindness to the social implications of science. 119 These were the source of " embarrassing contrasts in a society in which the hallmark of science is impatience with the status quo." 120 This embarrassment had basic guild implications, as one commentator noted: " The notion of the omnicompetence of the lawyer, cherished by the profession for centuries, is a myth." 121 Given this state of affairs, the coming of the Washington " superlawyers" 122 must have seemed far off indeed. In the near term, an altogether different story was being told: " Lawyers are losing caste" 123 and are " on the verge of plummeting in social importance," 124 though it remained to be seen whether science would, in fact, " reduce [them] to nothing more than electricians' helpers . . . ." 125 The rise of the scientific estate did more than threaten the prestige and independence of lawyers. It also challenged law's cherished self-conception as an instrumental, even constitutive force in society. An orbit around the moon convinced Frank Borman, of Apollo 8, that " [m]an can now do technology], the profession will abdicate its position of primary responsibility for creating and enforcing the rules by which society governs itself." ); Morgenthau, supra note 75, at 1406 (" The ascendancy of the scientific elites, then, is a function not only of their monopoly of esoteric knowledge, but also of the abdication, in the face of it, of the politically responsible authorities and of the politically conscious public." ). 115. Earl Warren, Science and the Law: Change and the Constitution, 12 J. PUB. L. anything he wants to technically." 126 This was to some extent the technocrat's article of faith, one that " subtly shifts the emphasis of the persistent political question 'Can we do this?' from the consideration of legal constraints to consideration of physical constraints." 127 In this limited sense, the technocrat's " one best method" participated in the postwar period's notorious " end of ideology" 128 both at home and abroad. Instrumental reason promised to depoliticize the management of public affairs and render obsolete-or at least inconsequential-the kind of complex normative disputes in whose resolution lawyers claimed to specialize. 129 In the view of some, the legal estate had already yielded its traditional authority to this false promise of positivism and engineered consensus, at the very least in the realm of technology policy, 130 if not in American governance more generally. Leon Lipson was reportedly fond of saying that " '[s]pace is a place, not a topic.'" 131 Lipson's remark may be understood as part of his attempt to reign in some of the especially fantastic ideations that characterized early space law. Yet outer space was more than just a geographical concept in the 1960s. The recent " spatial turn in critical thinking" 132 129. This version of the end-of-ideology thesis was emphasized most often by critiques of the thesis. See, e.g., Robert A. Haber, The End of Ideology as Ideology, in THE END OF IDEOLOGY DEBATE, supra note 128, at 182, 183 (attributing to the end-of-ideology thesis the argument that " the problems which are pressing for the society are of high complexity, do not have clear solutions, and political methods don't appear the most fruitful means of treatment" ); Stephen W. Rousseas & James Farganis, American Politics and the End of Ideology, in THE END OF IDEOLOGY DEBATE, supra note 128, at 206, 207 (citing Lipset's claim that " the ideological issues dividing left and right [have] been reduced to a little more or a little less government ownership and economic planning" ). 132. Edward Soja, Symposium: Surveying Law and Borders-Afterword, 48 STAN. L. REV. 1421, 1423 (1996) (" The spatial turn-or what might be called the spatialization of critical studies-reflects the growing interest in the power of space and spatial thinking as a way of interpreting not just the contemporary world, but of dealing with critical questions of all kindsincluding those addressed by critical legal scholars. Increasing attention is being given to the problems of the city, urban and regional issues, to locality, to the body, to place, to the The Yale Law Journal [Vol. 108: 1737 elsewhere should help us to appreciate that outer space was also a thoroughly politicized and socially constructed realm. As the Soviet and American culture industries of the time knew all too well, space functioned primarily as a metaphor for the future, and for the scientific worldview-be it capitalist or communist-that would dominate that future. Ludwig Teller attested to this construction of space in the New York Law Forum: Space is no longer an ordinary word of the English language. It has taken on a secondary meaning identified with the science and technology of astronautics and expressive of the awesome responsibilities which missiles and satellites and flight beyond the earth's atmosphere and into the mysterious reaches of outer regions have imposed upon us. Who controls space controls the world. 133 Indeed, " space" was a topic. To the extent that it was a metaphor for the scientific future, outer space was also a metaphor for the profound challenges that this future presented to the status of legal knowledge. By the unparalleled force of its technological spectacles, space exploration helped establish science as a center of political and normative authority. At the same time, it opened up a new geography, the geography of the future, that seemed intelligible only to scientific knowledge. This put the legal estate on the defensive, and challenged the traditional prerogatives of law's empire itself. The scientific frontier in outer space promoted in the popular imagination on Earth an alternative language of command, a new standard of authority and competence, and a new force for the construction of the future. As the Sputnik crisis suggests, space exploration was local, as much for the scientific culture in orbit as for the legal culture on the ground. Two factors help to explain why the legal estate reacted so closely to the arrival of the Space Age. The first was that Apollo-era space-law commentators failed to realize, as did most of the world at the time, that the imminence of extraterrestrial colonization, industrialization, and militarization was a " fabricated illusion." 134 This illusion was fostered in order to justify the enormous sacrifice of public capital necessary to fuel space exploration and win the space race. 135 The astrophysicist James Van Allen did his best to debunk this illusion in testimony before Congress: " I do not subscribe to some 99% of what is written about this subject-space relationships between the local and the global, to boundaries, to borders, to what can most broadly be described as the spatiality of human life." ). 133 exploration-as having any validity." 136 Notwithstanding such voices of dissent, space lawyers believed the hype (indeed, contributed to it) and sought to acculturate to the law the ninety-nine percent that Van Allen ridiculed. To be sure, this was a losing proposition. After all, how do you reduce to an object of law the utopian visions of science fiction? The ninety-nine percent described a future dedicated to " [t]he accelerating momentum of history, the figurative shrinking of the globe, the telescoping of time," 137 a future that would transcend the law's traditional dictum ex facto jus oritur, that the law arises out of the fact. As the space politician Emilio Daddario urged, " we must build a body of law which can be reconciled with facts we have yet to learn about the world of outer space." 138 The legal profession's fate, in other words, would henceforth be a struggle to anticipate and bring within the law a new era of overwhelming technological, cultural, and geographical discontinuity-an era, in more recent terms, of " cyberspace" and " cybertime." 139 A second, closely related condition concerned what this seemingly inevitable future implied about the law's present. The common aphorism of the Space Age, " Who controls space controls the world," 140 was underwritten by a subtle post-Orwellian message: Who controls the future controls the present. Space was the new high ground in more than just military terms. It was also an ethical or normative high ground, the blankness on which Space Age culture could project its " image of the 136. JAMES VAN , 1998) (" The present epoch will perhaps be above all the epoch of space. We are in the epoch of simultaneity: we are in the epoch of juxtaposition, the epoch of the near and far, of the side-by-side, of the dispersed. We are at a moment, I believe, when our experience of the world is less that of a long life developing through time than that of a network that connects points and intersects with its own skein. One could perhaps say that certain ideological conflicts animating present-day polemics oppose the pious descendants of time and the determined inhabitants of space." ). 140 141 To its great credit, early space law seems to have operated according to this principle. It feared the dominance of science and technology not only in the future as it would be lived, but also in the future as it was currently being imagined, mapped out, advertised-the future as it existed in the present. In this sense, the legal profession sought to intervene in the construction of a purely scientific image of the future, lest this prophesy become self-fulfilling. The law's post-Sputnik reaction may appear comical to our eyes, in that it lent credence to the fabulous ninetynine percent, 142 in that it took the eccentric worldview of science fiction at its word. Yet this merely indicated the extent to which lawyers at the time understood the stakes involved. Fearful of being augured out of the Space Age, and mindful of the popularity of Futures Studies in the 1960s, 143 they shrewdly sought to exploit the possibility that, as one space lawyer wrote, " the idea of law is a picture of the future." 144 In thus calling into question the sufficiency and scope of legal knowledge, the Rocket State posed a profound challenge to what Peter Fitzpatrick has called the " mythology of modern law." Fitzpatrick locates this mythology within the framework of the colonial imagination: 145 Thus modern law emerges, in a negative exaltation, as universal in opposition to the particular, as unified in opposition to the diverse, as omnicompetent in contrast to the incompetent, and as controlling of what has to be controlled. . . . Law is imbued with this negative transcendence in its own myth of origin where it is imperiously set against certain " others" who concentrate the qualities it opposes. Such others are themselves creatures of an Occidental mythology, a 141. Cf. 1 FRED L. POLAK, THE IMAGE OF THE FUTURE: ENLIGHTENING THE PAST, ORIENTATING THE PRESENT, FORECASTING THE FUTURE 31 (Elise Boulding trans., 1961) (" It is the positive ideas and ideals of man, cast in the form of images of the future, picturing another and better world to come, which have here largely made history what it is. . . . [T]o the extent that these perfectionist and idealistic images of the future have served as predominating motifs and guiding stars to the societies which have held them, they have indeed been active in shaping the future for those societies." ); 2 id. at 115 (" The prevailing positive images of the future, perpetually breaking through the frontiers of time, have formed powerful-often the most powerful-long-range dynamic force pushing history through time. . . . [T]he history of culture is the history of its images of the future." ). 142. mythology which denies its own foundation by consigning myth in general to the world of these others. 146 This " negative transcendence" is the " fateful dimension" that the Enlightenment project sets for itself, explains Fitzpatrick. " [W]ith its claims to a sole rationality, to universality, comprehensiveness and consistency . . . [i]t can only relate to that part of nature which persistently stands outside of its project, which persistently denies it, as something essentially 'other.'" 147 The culture of space exploration made untenable law's claim to universal modernity. If the rhetoric of the Rocket State was to be believed-and for the most part it was believed-then law itself had become a kind of colonial other. It had begun to " concentrate the qualities it opposes." In the judgment of science, its mentality was " savage, primitive, underdeveloped." 148 In its own judgment, its origins were " ancient," its " omnicompetence" was a " myth," its likely fate was " oblivion." No longer could it claim possession of " the arcana imperii." 149 Instead, to expound legal knowledge in the Space Age was to preach the beliefs of the " stone age." 150 To restore legal knowledge was to demand that it " give up its present unscientific form and join with science in the cooperation of man with man in the conquest of nature." 151 In the most general terms, then, the Space Age violated, however briefly, law's traditional sense of empire. In the blankness of outer space, legal knowledge confronted a twentieth-century heart of darkness that formed an all-encompassing periphery to its claims to universality, omnicompetence, and centralism. This periphery was no savage darkness, however. On the contrary, it described the " endless frontier" 152 of scientific enlightenment. It was a kind of empire unto itself, and one with a future. Commenting on the outpouring of writing on space law in the wake of Sputnik, Euthymène Georgiades observed that " jurists, it appears, like nature, abhor a vacuum." 156 This Part examines the ways in which legal knowledge rushed in to fill this vacuum. The overriding assumption of this Part is that early space-law commentary sought only incidentally to state a coherent doctrine of space law. The equitable distribution of craters on the moon was not its primary concern. Rather, Apollo-era space law was cultural work. It sought to affirm the legal estate's " capacity to persuade people that the world described in its images and categories is the only attainable world in which a sane person would want to live." 157 This meant the extension of legal images and categories, of legal discourse, into the discursive field of outer space. For better or worse, it meant the strange " imbrication" of legal meaning into a culture of space exploration. 158 Section A considers space law's attempt to establish a boundary between atmospheric space and outer space. Section B discusses the attempt to codify space law. Section C concludes by examining early space law's effort to defend the legal rights of extraterrestrial civilizations. In the early years of space law, variations on this question entitled innumerable popular and scholarly publications throughout the West, 159 much to the chagrin of Chairman Krushchev, who declared himself too historically advanced to consider the issue. 160 Of course, Krushchev had a point. The question of ownership tended to function in the West as the catchall for a wide variety of inquiries into more specific issues relating to extraterrestrial sovereignty, jurisdiction, conflict of laws, and property rights. Such inquiries typically began with a question that remains unresolved to this day: Where does sovereign airspace end and outer space begin? The question of atmospheric sovereignty received " more attention from the legal writers than any other space law problem." 161 In the process, it provoked a chaos of unsatisfactory answers, indeed " a complete lack of authoritative prescriptions." 162 The most bizarre of such prescriptions was the notion of space-cone sovereignty, in which the classical doctrine cujus est solum, ejus est usque ad coelum (" he who owns the land, owns it to the skies" ) enjoyed an enormously expansive and latter-day Ptolemaic reading. 163 160. To a reporter's question concerning whether Luna 2's impact on the surface of the moon signaled a Soviet intent to claim possession, Krushchev responded: I do not want to offend anybody, but we represent different continents and different psychologies, and I would say that this question reflects capitalist psychology, of a person thinking in terms of private ownership. But I represent a Socialist country, where the word " mine" has long receded in the past and the word " our" has taken its place, and therefore when we launched this rocket and achieved this great thing, we look upon this as our victory, meaning the victory not only of our country but of all countries of all mankind. Remain in Orbit!, MIL. L. REV., Jan. 1960, at 23, 25 (" Since commencement of the venture into upper areas of space-marked by the blast-off of Sputnik I on October 4, 1957-the pages of law reviews and political journals have been drenched with writings concerning the problem of the extent of national sovereignty into space." ). 162. Gorove, supra note 140, at 328. 163. " This hypothesis is accomplished by projecting a nation's boundaries upward perpendicularly to the earth's surface from the center of the earth through the nation's boundaries to infinity." Joe C. Savage, Note, Legal Control of Outer Space, 52 KY. L.J. 404, 409 (1964). Of the concept of space-cone sovereignty, C. Wilfred Jenks observed: " Such a projection into space of sovereignties based on particular areas of the earth's surface would give us a series of adjacent irregularly shaped cones with a constantly changing content. Celestial bodies would move in and out of these cones all the time." C. Wilfred Jenks, International Law and Activities in Space, 5 INT'L & COMP. L.Q. 99, 103 (1956); see also United States v. Causby, 328 U.S. 256, 261 (1946) (declaring that the cujus est solum doctrine has " no place in the modern world." ). Still, the notion of the space cone had its uses. Consider, for example, the reasoning of Franco Fiorio: But the " size and power" criteria, too, lose significance in the true space age, because the cone of space rising over the vertical of the territory of a small country like the Republic of San Marino, expands to infinite size at the outer reaches of the universe The Yale Law Journal [Vol. 108: 1737 reasonable, that Sputnik did not orbit over the United States, but rather that the United States rotated under Sputnik. 164 Most commentators, in contrast, sought to establish an altitudinal boundary between sovereign airspace and the res nullius, res communis, or res extra commercium of outer space. To do so, they typically began with the alleged constants of geophysical and astronomical science. A common proposition was that airspace sovereignty should simply end where " airless outer space" 165 begins-notwithstanding the fact that, as Arthur C. Clarke observed at the time, it is no more possible to establish " where the atmosphere ends than one can define the moment when a musical note ceases." 166 A related and equally suspect proposal sought to limit sovereignty to the " point of nullity of the field of gravity." 167 Other commentators sought to calibrate sovereignty according to technological variables. Thus, sovereignty should end at the minimum altitude necessary for orbit, 168 at the maximum altitude at which aerodynamic lift is available, 169 or at the farthest technological reach of the subjacent nation 170 or of any nation. 171 Still others propounded elaborate regimes of " zones" or " belts." Arnold Knauth, for example, envisioned a scheme of as many as ten zones, starting with the " altitude to which an aircraft can lift a weight or cargo or military weapon," progressing through such boundaries as the " known orbit of the moon," and ending with " translunar space (ad infinitum)." 172 William Hyman urged the establishment of " Neutralia," which would function as a " buffer zone" between airspace just the same way as the cone of space rising from the territory of a large nation such as the United States of American [sic] or the Soviet Republic. Space is therefore a great equalizer and we feel that each nation, large or small, including San Marino, has the right to stand up and be heard on space problems. and outer space. 173 Finally, some commentators simply proposed arbitrary limits on airspace, at 30 miles, 174 50 miles, 175 , 100 miles, 176 or, as a 1961 Note in the Harvard Law Review suggested, 50,000 miles. 177 The boundary theorists were often ridiculed for their various efforts to maintain " astrolegal" appearances. Writing in the American Bar Association Journal, Senator Keating was among the first to express dismay at the boundary theorists' " too-anxious desire to resolve at once the thorniest legal question-mark conjured up by our prototype activities in space . . . ." 178 Others shared in Keating's frustration. Harold Caplan feared that law would cede outer space to science: " The indications are that scientists, left largely to themselves, could evolve a code of human conduct for peaceful activities in space. . . . Will scientists leave the jurists stranded on the earth interminably arguing about the upper altitude limit for sovereignty?" 179 The aviation authorities Sir William Hildred and Sir Frederick Tymms equated the efforts of the boundary theorists with the notorious failures of early twentieth-century air law, in which the height of the Eiffel Tower and the vertical range of artillery had been proposed as the altitudinal extent of sovereignty. 180 Inevitably, the Wall Street Journal was left smugly to compare the sovereignty debate to the Old World's apparently futile attempt to divide up the territories of the New. 181 Yet the question of atmospheric sovereignty dominated early legal headlines on outer space, and elaborate maps of the proposed legal divisions of near-Earth outer space appeared throughout the literature. 182 Why? Sputnik alone may provide the answer. Orbiting on the periphery, the artificial satellite nevertheless threatened to take over-or at least, definethe center. It had to be legalized. That much was obvious. What is peculiar, however, is the form of legalization that so many early space-law commentators proposed. Rather than regulate conduct according to some theory of functional sovereignty, 183 rather than control for such specific activities as surveillance or militarization, the preponderance of legal thought sought, in the first instance, to map space, to provide " purely The Yale Law Journal [Vol. 108: 1737 spatial solutions." 184 Perhaps this was simply an attempt at consolidation: Inside the limits of the atmosphere was the rule of law; outside was the " law of the jungle." 185 The " spatial turn" in legal thinking supports an alternative explanation: This act of mapping was an attempt-and a very traditional one-to expand the empire and circumscribe what lay beyond its frontiers. 186 Like the latitude and longitude of Western cartography, the map provided legal commentators on outer space with " a symbolic statement of power and dominion." 187 It placed borders where science could not and renamed for the law the regions that science had always claimed as its own. In short, it inscribed the legal " topic" onto the scientific " place." The motivations that underlay law's mapping of outer space help to explain something else: all the loose talk of ownership. The compulsive reference in the West to " who owns what" 188 and " what space is whose" 189 was more than just the panicked response of a capitalist ideology being overflown by a Soviet satellite. In the improbable notion of ownership of a vacuum, the legal estate brought to bear on the phenomenon of space exploration perhaps the most persuasive rhetoric available to law, Western or otherwise: the rhetoric of property. Be it " mythic" in its political valence 190 or merely the lowest common denominator of popular legal culture, 191 property talk had the power to reduce even Tranquillity Base to a question of legal possession. Notions of sovereignty may have been more appropriate, but they were a poor substitute for a mode of rhetoric in which, it has been suggested, " Property is Persuasion." 192 In a culture of space exploration, property talk served several purposes. At a basic level, it assisted in the law's cartographic ordering of chaos. It perpetuated an age-old process in which, as Fitzpatrick argues, " the joint advance of civilization and law in progressive opposition to various savage and barbaric stages is comprehensively mapped in terms of property." 193 Property talk also formed a kind of distraction from the utopian promise of the scientific frontier. 194 It told a story in which outer space would not function as a realm of infinite technological and libertarian plenitude-a realm where humankind might transcend its competition for resources, and perhaps even bring about the " gradual disappearance of the juridic element in human relationships." 195 Rather, space lawyers envisioned outer space as a finite common, already overcrowded with " sooners," 196 that required strict borders, clear rules, and property-based incentives for efficient exploitation. Notwithstanding Krushchev's idealism, early space law in the West insisted on viewing outer space as a potential " tragedy of the commons" and predicted, to use a cyberlawyer's recent phrase, the " economics of constraint." 197 Space law did so in honor of where the rule of law begins and of what would be its " great and chief end." 198 Who owns the universe? Law owns the universe. The Legal-Humanist "Counterrevolution" By 1960, the failure of any nation to protest Sputnik I and its successors had effectively suspended the debate over the altitudinal extent of national sovereignty. Space law moved on, from the map to the code. The focus of the debate shifted to the question of customary law versus codification. Should lawyers " permit the concept of Space regulation to 'just grow,'" 199 or should they allow science to " stampede [them] . . . into attempting, prematurely, a statement of space law?" 200 203 in which he contemplated the establishment of rules regulating such matters as the placement in orbit of " Kunstmonde," 204 or artificial satellites, and the timing of death declarations and insurance arrangements for outer-space travelers. 205 As a space-law theorist, Mandl lived before his time, but not by much. By the early 1960s, highly specialized debates had formed around such issues as extraterrestrial jurisdiction, radio-spectrum control, space torts, and the registration and identification of spacecraft (lest a launch be mistaken for a preemptive nuclear strike). 206 Disputes also arose over which 201. McDougal was the leading exponent of the incremental development of space law. In Perspectives for a Law of Outer Space, he and Leon Lipson advocated " the slow building of expectations, the continued accretion of repeated instances of tolerated acts, and the gradual development of assurance that certain things may be done under promise of reciprocity and that other things must not be done on pain of retaliation." McDougal & Lipson, supra note 11, at 420 (citation omitted). The article forcefully rejected the feasibility of a comprehensive space code: A durable agreement by explicit international convention on anything like a code of law for outer space is not, in our opinion, something now to be expected or desired. One may indeed expect with rather more confidence a series of agreements, gradually arrived at, on particular subjects . . . . . . . . The modes of reaching such agreements cannot now be charted with any precision. Some agreements may be explicit and formal; some may be simply a consensus achieved by the gradual accretion of custom from repeated instances of mutual toleration. Some may be bilateral, others trilateral or multilateral; some may be within the framework of the United Nations, others within some other existing organization or some machinery yet to be set up. international agency should interpret and enforce space regulations. 207 Among the advocates for codification, the Canadian Maxwell Cohen was probably the leading voice. He argued that the accelerating pace of technology had rendered the methods of international customary law largely obsolete in outer space. 208 William Hyman took a different tack. In his view, the " space law gap" 209 was the result of " sheer cowardice on the part of the profession" 210 typified by the " anti-space law forces" 211 within the American Bar Association. Those who opposed codification, such as the " collaborating pair of professors of law," 212 were no better than early opponents of child labor laws. 213 These were strong opinions, yet the alternatives to codification seemed unthinkable: the possibility of orbiting missile platforms or of Cold War tensions brought to the breaking point by surveillance satellite overflights. In their own, peculiar effort to assert the continued vitality of the legal profession in the Space Age, the space-law codifiers presented lawyers as those professionals uniquely capable of investing outer space with the humanist values that it would otherwise lack. That is to say, having been stigmatized or " othered" by the science of the time, law stigmatized in turn. It represented science as amoral, antihumanist, and dystopian. In the process, it adjusted the traditional fatalism of " death of law" rhetoric to suit the age of technocracy and space exploration-and, later on, of civil disobedience and " culpable legicide." 214 Arthur Selwyn Miller, for example, declared that " we have reached the point where the future must be planned for in a humanistic sense. Our future is being planned for us by the The traditional time-scales characteristic of the slow processes of customary or conventional law-making have been altered by the rate of technological advance in the management of space. . . . . . . . . . . [W]hile man crossing the oceans could afford the luxury of two or three hundred years to evolve regimes of the high seas in the movement from mare clausum to mare liberum, and yet produce in consequence only five or six main principleswidely accepted, flexible and reasonable in their enforceability-no such leisurely pace is available to man exploring space. Here the urgencies, both positive and negative, require the early fashioning of agreed-upon rules which go beyond the capacity for effectiveness of broad customary principles standing alone. With the exception of William Hyman, 217 the codifiers were hardly the " lawyer militant[s]" 218 or science tamers that Miller or Schroeder had in mind. Still, they were not above coopting the countercultural rhetoric of antitechnology to defend their legal prerogative in outer space. Thus C. Wilfred Jenks cited the works of Franz Kafka and Eugène Ionesco to support the idea of codification. 219 Eilene Galloway quoted Arthur C. Clarke's The Challenge of the Spaceship to the effect that " '[m]orals and ethics must not lag behind science, otherwise the social system will breed poisons which will cause its own [sic] destruction.'" 220 And in a remarkable essay, in which he analyzed the spacepowers' " mutual exchange of scientific surveillance," Philip Yeager speculated that a space code might help stave off " the Orwellian nightmare of '1984.'" 221 Even Mandl, a selfstyled technocrat of the 1930s, 222 warned of the prospect of overmechanization and a time when " machines would strangle all living things." 223 The space-law codifiers may have sought to position the legal profession as, in some sense, the profession of the counterculture. Indeed, they may have welcomed the idea that, as one commentator put it, " devoting thought to developing space law is just a 'beatnik' manifestation of being 'far gone' and 'way out.'" 224 Yet as their faith in codification itself suggests, the codifiers were not entirely free from the technocratic temptation. On the contrary, their search for what Myres McDougal called the " Big-Solution-Now" 225 brought them squarely within the orthodoxy of the age, as did their appeal to the " machinery of detailed administration." 226 If they believed the hype of the Space Age, the codifiers believed also in the rising tide of " comprehensive rationality" and " policy science." 227 Thus they produced another characteristic graphic of early space law: the long, exhaustive outline of legal problems, both current and prospective, posed by space exploration. 228 Like the map and the bibliography, the outline was a rhetorical device. It suggested that legal knowledge could schematize the full chaos of space, order it according to the " 'A' to 'Z' in the lexicon of the law." 229 As a code in embryonic form, the outline asserted that, at least for the law, the Space Age would remain a closed system. If early space law defended the values of humanity in outer space, it claimed to defend the values of something else as well. Emboldened by a half-century of scientific writing on the possibility of exobiological life forms, 230 and by an age-old literature, both fictional and philosophical, on the " plurality of worlds," 231 space law populated the scientific object of outer space with legal, albeit extraterrestrial, subjects. True to its traditions, law's empire deduced the existence of the " other" and assumed that this " other" would be resolved, sooner or later, into a judicial question. Most Apollo-era space-law commentators took for granted the need to formulate a legal theory of extraterrestrial life forms. Some went so far as to suggest that Earth law must now be subsumed within a still mysterious cosmic or interplanetary law. 232 The aerospace industrialist and lawyer The Yale Law Journal [Vol. 108: 1737 Andrew Haley was closely associated with this latter effort. A leading popularizer of space law during the 1960s, Haley told The Washington Post that " [o]ne of the very first professional men the prospective colonizer of outer space is going to have to consult . . . is a metalawyer." 233 Elsewhere in his writings, he explained why this would be the case: " The indefinite projection of a system of anthropocentric law beyond the planet Earth would be the most calamitous act man could perform in his dealings with the cosmos." 234 It would constitute the extension into space of " the bleak and devastating geocentric crimes of mankind." 235 It risked " galacticide." 236 Thus, the golden rule itself must yield to the new order of metalaw: " We must do unto others as they would have done unto them." 237 The majority of commentators had little regard for metalaw. Harold Lasswell, for example, seemed more concerned with the possibility that " [g]uided TV programs" might be used to establish " empathy . . . among all members of the astropolitical arena." 238 Still, those lawyers who wrote about extraterrestrial civilizations must have found Haley's nearly messianic sensibility to be congenial. William Hyman spent much of his career propounding the Magna Carta of Space. Article 18 of this document stipulates that " [t]he peoples of the earth do hereby declare that they recognize the rights of sovereignty, ownership and control of any other planet by the inhabitants thereof." 239 Philip Yeager took this thinking to yet another level. He argued that it was one thing for a nation to claim jurisdiction over its adjoining islands, but it was something altogether different, and would, in fact, be " a rather cosmic-shaking event for one planet, or parts thereof, to assert dominion over another." 240 Such speculations inevitably led some Americans seriously to consider the possibility of a second American Revolution or the formation of independent states separate from Earth. In a 1958 address to the American Association for the United Nations, Arnold Knauth rejected the idea that there could be an " emperor or president of Outer Space," but contemplated the possibility that " [t]he first groups who go may make their own Mayflower Compacts." 241 Myres McDougal and Leon Lipson spoke of " wars of interplanetary independence." 242 What motivated this theorizing? Some tentative explanations may be proposed. Philip Yeager offers the beginnings of one. He urges that lawyers prepare for the possibility of life on the moon, if only because: [I]t would have the virtue of humility. It would not cast lawyers and political scientists in the poor light which some physical scientists have achieved by their narrow assumptions that no intelligent life can exist in the Solar system, or anywhere in the universe, except under the physical conditions and according to the physical laws which they themselves have thus far managed to observe. 243 Yet there was probably more to extraterrestrial space law than this professional one-upmanship over " physical scientists," or over practitioners of earthbound law. As Yeager's comment suggests, legal theory on extraterrestrials also participated in the era's larger " culture of dissent" 244 against, among other things, the totalizing knowledge-claims of the Rocket State. Recent work on American ufology in the 1950s and 1960s has shown how talk of extraterrestrials " established a space from which to resist the expert culture of containment and assert the authority of amateur and civilian opinion and research." 245 Whether already among us or yet to be encountered, extraterrestrial life forms bespoke scientific and spiritual mysteries undreamt of by systems analysis. 246 In this sense, legal 241. Knauth, supra note 29, at 261. Earlier in the address, Knauth presented his vision of the politics of spacemen: Outer space is going to be like the top of Mount Everest, a place to which a man goes briefly to conquer or to die, and to which he does not take his wife and children, nor where he sets up a stock exchange brokerage house. I do not know anyone who foresees a local political village life in outer space, or who expects to set up a grammar school, a high school, and a college there. These spacemen will follow their own ideas as to safety and will assume calculated and uncalculated risks; they will be hardy fellows, and are not likely to heed the recommendations of a Secretariat. If their enterprise fails, they will never face a board which wants to punish them; if they return safely, they will be heroes to many if not to all. (1998); see also ENGELHARDT, supra note 66, at 104 (" The 'ufologists' were also almost the only group at the time to take on the national security state directly, assailing the secrecy that surrounded the government's UFO investigations and claiming a cover-up of information relating to the reality of space aliens." ). 246. Cf. ERIK DAVIS, TECHGNOSIS: MYTH, MAGIC AND MYSTICISM IN THE AGE OF INFORMATION 229 (1998) (" Keeping midcentury fears about nuclear apocalypse in mind, the commentary on extraterrestrials expressed the full ambition of law's empire. It projected the rule of law and lawyers into the cosmos, and sought to establish legal knowledge over the unknown and the unimaginable. There would be no blank spaces on the law's map of outer space, no unregulated commons, no unregulated anything. Such principles as Ernst Fasan's " eleven rules of Metalaw" 247 would assimilate the universe itself, and those who still spoke of " natural law" simply lacked vision. Apollo-era legal theory on extraterrestrials thus constituted a kind of transcendental imperial principle: The " myth of modern law" became, in Andrew Haley's words, the " rule of law governing all creation." 248 To view Apollo-era legal commentary on extraterrestrials through the lens of the postcolonial helps to explain perhaps the most striking peculiarity of early space law: that Latin American commentators figured so prominently in the movement, and formed in fact their own distinctive school of thought. Myres McDougal would probably have classified some Latin American nations as among those for whom effective control " would end at the treetops," 249 and, it is true, only Brazil had any space policy worth mentioning. Yet the likes of the Argentinian Aldo Armando Cocca, the Uruguayan Alvaro Bauza Araujo, and the Brazilians Hésio Fernandes Pinheiro and Haraldo Valladão were leading voices in international space law. Their work deserves an extended treatment, if only to recognize their practice of subverting the terminology of first-world space law, and international law with it. What must be noted here is their overriding concern with the rights of extraterrestrial civilizations. Against the backdrop of postwar decolonization, dependency, and, in smaller measure, liberation theology, these commentators found in space law a means of resisting " the ideas of sovereignty, predominance, appropriation of territories and enslaving of the respective inhabitants, which maculated the birth of International Law in the XVth and XVIth Century." 250 For them, space exploration meant nothing less than jus novum, both in the heavens and on earth: UFO must also be seen as a visionary projectile hurtling from the unconscious depths of the information age. . . . The UFO, it seems, is a rumor of God stitched into the fabric of the militaryindustrial-media complex, a complex whose cybernetic tentacles encircle us still." ). 247. FASAN, supra note 237, at 71. 248. HALEY, supra note 201, at 411. 249. MCDOUGAL ET AL., supra note 2, at 342 (" If every state were allowed to project its sovereignty upward and sideward in accordance with its effective power, there would inevitably arise countless conflicting claims with no criteria for their accommodation other than naked power. Moreover, for many underdeveloped states sovereignty would end at the treetops, while for a handful of the most powerful states, not even the sky would be the limit." ). First of all, it is important to stress that Space Law is of a planetary nature as well the only truly universal law. It concerns human beings as such, either in the Earth or during cosmic travels, regardless of the geographical latitude or position in space. Space law does not take into account technological or economic development. No doubt it is a total law: a jus humanitatis, the law of mankind. 251 As voices of intervention in the dominant global narrative of technological advance, these commentators spoke from the visionary center of Apollo-era space law. Indeed, in the beginning, all of space law was, in some sense, Latin American. Through all Eternitie so late to build In Chaos -John Milton, Paradise Lost 252 This Note may seem a loser's history. The " golden age" of the Corpus Juris Spatialis passed as quickly as it came and is now for the most part forgotten. The Rocket State has developed ever more accurate ballistic missiles, but no jus novum. Modern space law has evolved, at its best, into a highly technical discourse spoken primarily by specialist practitioners. The futurist idealism remains in the literature, as does the insistence on lawyerly prerogative, but it is the message of telecommunications in space that pays for the medium. Still, the legacy of Apollo-era space law remains vital, and for possibly obvious reasons. The millennial, recently apocalyptic rhetoric of the " Information Age" at least equals that of the Space Age. The implications for law's empire are thought to be as grave. Be it in the form of the borderless " electronic frontier" of cyberspace or the monster hypotheticals posed by the Human Genome Project, information technology challenges the competence and universalist ambition of legal knowledge, threatening a profound reversal in the law's " informational fate." 253 Indeed, the " civilization of the Mind in cyberspace" 254 has already declared its Against whatever new enlightenment is being proclaimed by technology, legal knowledge thus tends to effect a romantic reaction, but one that is itself undertaken in the name of " righteousness, discipline, order, and well-articulated theory." 266 Ever the imperialist, it talks not so much about the future as through it. Ever the proprietor, it invokes law itself as the magic solving word that can rationalize chaos and whatever might lie beyond it. As what " [w]e live in and by" 267 or, alternatively, " as reason encoded in the doings and dreams of power," 268 law insists all the while that its own talking cure is also curative of technological cultureand if not curative, than at least constitutive. A defense of the constitutional rights of genetic " sub-human" laborers, 269 a vision of the human genome as the common heritage of humankind 270 -the profession should hardly judge these for the extent to which they manage a coherent statement of legal doctrine. The lex ferenda 271 that grows out of this futurist imaging may never be promulgated, let alone enforceable. Yet if the estate and its empire are to survive, then it must acculturate the future to the law even as it indoctrinates the present, and to do so, it must honor where the rule of law begins and what may continue to be its " great and chief end." REV. 396, 411 (1963). 35. MCDOUGAL ET AL., supra note 2. 36. Richard Posner, Law and Public Order in Space, 77 HARV. L. REV. 1370, 1373 (1964) (reviewing MCDOUGAL ET AL., supra note 2). 48. DAVID T. NYE, AMERICAN TECHNOLOGICAL SUBLIME 256 (1994) (" In an atomic age, the pilgrimage to the Kennedy Space Center promised a sublime experience that renewed faith in ). 49. RALPH E. LAPP, THE NEW PRIESTHOOD: THE SCIENTIFIC ELITE AND THE USES OF POWER (1965); see also SPENCER KLAW, THE NEW BRAHMINS: SCIENTIFIC LIFE IN AMERICA (1969); DON K. PRICE, THE SCIENTIFIC ESTATE (1965); Jack Raymond, The "Military-Industrial Complex": An Analysis, N.Y. TIMES, Jan. 22, 1961, at 4E (citing Eisenhower's reference to the " scientific-technological elite" ); Robert C. Wood, Scientists and Politics: The Rise of an Apolitical Elite, in SCIENTISTS AND NATIONAL POLICY-MAKING 41 (Robert Gilpin & Christopher Wright eds., 1964). 50. Meg Greenfield, Science Goes to Washington, in THE POLITICS OF SCIENCE: READINGS IN SCIENCE, TECHNOLOGY AND GOVERNMENT 124, 133 (William R. Nelson ed., 1968). 51. This term is adapted from Pierre Bourdieu. See generally Richard Terdiman, Translator's AND POLITICS 111 (Jeremy J. Shapiro trans., Heinemann Educ. Books 1971) (1968). 56. See generally HERBERT MARCUSE, ONE-DIMENSIONAL MAN: STUDIES IN THE IDEOLOGY OF 83. NORMAN MAILER, OF A FIREON THE MOON 471 (1970). 84. See, e.g., GUY BENVENISTE, THE POLITICS OF EXPERTISE (1972); JACQUES ELLUL, THE TECHNOLOGICAL SOCIETY (John Wilkinson trans., 1967); VICTOR C. FERKISS, TECHNOLOGICAL The Yale Law Journal [Vol. 108: 1737 variety of forms. MAN: THE MYTH AND THE REALITY (1969); HABERMAS, supra note 55; MARCUSE, supra note 56; JEAN MEYNAUD, TECHNOCRACY (Paul Barnes trans., 1968); THEODORE ROSZAK, THE MAKING OF A COUNTER CULTURE: REFLECTIONS ON THE TECHNOCRATIC SOCIETY AND ITS YOUTHFUL OPPOSITION (1969). 85. See GOULDNER, supra note 54, at 251-52. 86. See MARCUSE, supra note 56, at 3 (" By virtue of the way it has organized its technological base, contemporary industrial society tends to be totalitarian." ); see also 91. See, e.g., Wolf Haber, A Draft Convention on International Law of Space, MICH. ST. B.J., Mar. 1959, at 24; Kenneth B. Keating, The Law and the Conquest of Space, 30 N.Y. ST. B. BULL. J. 72 (1958); G. Vernon Leopold & Allison L. Scafuri, Law for the Space Age, MICH. ST. B.J., 92. See, e.g., Max Chopnick, Satellites and the Law of Space, A.B.A. SEC. INT'L. & COMP. LJ. 317 (1958). 93. See, e.g., John Cobb Cooper, Flight-Space and the Satellites, 7 INT'L & COMP. L.Q. 82 (1958); John Cobb Cooper, 98. Id. at 73. 99. Id. 100. Homer G. Angelo, Chairman's Message, A.B.A. SEC. INT'L & COMP. L. BULL., 123. Miller, supra note 111, at 615. 124. Arthur Selwyn Miller, Science and Legal Education, 19 CASE W. RES. L. REV. 29, 38 (1967). 125. Loevinger, supra note 96, at 541. 134. Thomas Merton, Comment to Why Some Look Up to Planets and Heroes,108 AMERICA 433, 433 (1963).135. See generally KAUFFMAN, supra note 47 (discussing NASA's public relations strategies); MCCURDY, supra note 47 (same). 151. Thomas A. Cowan, Law and Technology: Uneasy Leaders of Modern Life, 19 CASE W. RES. L. REV. 120, 124 (1967). 152. VANNEVAR BUSH, SCIENCE: THE ENDLESS FRONTIER (1960). The 159. See, e.g., Sidney Katz, Who Owns It, Anyway?, MACLEAN'S, Jan. 18, 1958, at 13; Arnold W. Knauth, 171. See Ming-Min Peng, Le Vol a Haute Altitude et l'Article 1 de la Convention de Chicago, 1944, 12 R.B.P.Q. 277, 292 (1952). 172. Arnold Knauth, Comment, in INTERNATIONAL LAW ASS'N, REPORT OF THE FORTY-NINTH CONFERENCE 264, 264-65 (1961).

A. The Birth of the American Rocket State

Big Science and the Law's "Cultural Cringe"

C. Scientific Space and the Mythology of Modern Law

C. Brooding Omnipresences: The Legal Status of Extraterrestrial Civilizations

IV. INFORMATIONAL FATE: WHO OWNS THE FUTURE?


"Learning Optimal Dialogue Strategies: A Case Study of a Spoken Dialogue Agent for Email," in Proceedings of COLING/ACL '98 (1998) (with Marilyn A. Walker & Shrikanth Narayanan)

"Learning Optimal Dialogue Strategies: A Case Study of a Spoken Dialogue Agent for Email," in *Proceedings of COLING/ACL '98* (1998) (with Marilyn A. Walker & Shrikanth Narayanan)

Marilyn A. Walker et al., Learning Optimal Dialogue Strategies: A Case Study of a Spoken Dialogue Agent for Email, in Proceedings of COLING/ACL '98 (1998)

Marilyn A. Walker
Jeanne C. Fromer
Shrikanth Narayanan

This paper describes a novel method by which a dialogue agent can learn to choose an optimal dialogue strategy. The main problem for dialogue agents is deciding what information to communicate to a hearer and how and when to communicate it. For example, consider one of the strategy choices faced by a spoken dialogue agent that accesses email by phone. When multiple messages match the user's query, e.g. Read my messages from Kim, an email agent must choose among multiple response strategies. The agent might choose the Read-First strategy in DI: (D1) A: In the messages from Kim, there's 1 message about "Interviewing Antonio" and 1 message about "Meeting Today:' The first message is titled, "Interviewing Antonio:' It says, 'Td like to interview him. I could also go along to lunch. Kim:' D1 involves summarizing all the messages from Kim, and then taking the initiative to read the first one. Alternate strategies are the Read-Summary-Only strategy in D2, where the agent provides information that allows users to refine their selection criteria, and the Read-Choice-Prompt strategy in D3, where the agent explicitly tells the user what to say in order to refine the selection: (D2) A: In the messages from Kim, there's 1 message about "Interviewing Antonio" and 1 message about "Meeting Today:' (D3) A: In the messages from Kim, there's 1 message about "Interviewing Antonio" and 1 message about "Meeting Today:' To hear the messages, say, "Interviewing Antonio" or "Meeting." Decision theoretic planning can be applied to the problem of choosing among strategies, by associating a utility U with each strategy (action) choice and by positing that agents should adhere to the Maximum Expected Utility Principle (Keeney and Raiffa, 1976;Russell and Norvig, 1995), An optimal action is one that maximizes the expected utility of outcome states. An agent acts optimally by choosing a strategy a in state Si that maximizes U(Si). But how are the utility values U(Si) for each dialogue state Si derived? Several reinforcement learning algorithms based on dynamic programming specify a way to calculate U(Si) in terms of the utility of a successor state Sj (Bellman, 1957;Watkins, 1989;Sutton, 1991;Barto et al., 1995). Thus if we know the utility for the final state of the dialogue, we can calculate the utilities for all the earlier states. However, until recently there as been no way of determining a performance function for assigning a utility to the final state of a dialogue. This paper presents a method based on dynamic programming by which dialogue agents can learn to optimize their choice of dialogue strategies. We draw on the recently proposed PARADISE evaluation framework (Walker et al., 1997) to identify the important performance factors and to provide a performance function for calculating the utility of the final state of a dialogue. We illustrate our method with a dialogue agent named ELVIS (EmaiL Voice Interactive System), that supports access to email over the phone. We test alternate strategies for agent initiative, for reading messages, and for summarizing email folders. We report results from modeling a corpus of 232 spoken dialogues in which ELVIS conversed with human users to carry out a set of email tasks. Our method for learning to optimize dialogue strategy selection combines the application of PAR-ADISE to empirical data (Walker et al., 1997), with algorithms for learning optimal strategy choices. PARADISE provides an empirical method for deriving a performance function that calculates overall agent performance as a linear combination of a number of simpler metrics. Our learning method consists of the following sequence of steps: • Implement a spoken dialogue agent for a particular domain. • Implement multiple dialogue strategies and design the agent so that strategies are selected randomly or under experimenter control. • Define a set of dialogue tasks for the domain, and their information exchange requirements. Represent these tasks as attribute-value matrices to facilitate calculating task success. • Collect experimental dialogues in which a number of human users converse with the agent to do the tasks. • For each experimental dialogue: -Log the history of the state-strategy choices for each dialogue. Use this to estimate a state transition model. -Log a range of quantitative and qualitative cost measures for each dialogue, either automatically or with hand-tagging. -Collect user satisfaction reports for each dialogue. • Use multivariate linear regression with user satisfaction as the dependent variable and task success and the cost measures as independent variables to determine a performance equation. • Apply the derived performance equation to each dialogue to determine the utility of the final state of the dialogue. • Use reinforcement learning to propagate the utility of the final state back to states Si where strategy choices were made to determine which action maximizes U(Si). These steps consist of those for deriving a performance function (Section 3), and for using the derived performance function as feedback to the agent with a learning algorithm (Section 4). ELVIS is implemented using a general-purpose platform for spoken dialogue agents (Kamm et al., 1997). The platform consists of a speech recognizer that supports barge-in so that the user can interrupt the agent when it is speaking. It also provides an audio server for both voice recordings and text-tospeech ('I~I'S), an interface between the computer running ELVIS and the telephone network, a module for application specific functions, and modules for specifying the application grammars and the dialogue manager. Our experiments are based on modifications to the dialogue manager as described below. The dialogue manager is based on a state machine. Each state specifies transitions to other states and the conditions that license these transitions, as well as a grammar for what the user can say. State definitions also include the specification of agent prompts in terms of templates, with variables that are instantiated each time the state is entered. Prompts include: (1) an initial prompt, which the agent says upon entering the state (this may include a response to the user's current request); (2) a help prompt which the agent says if the user says help; (3) multiple rejection prompts which the agent says if the speech recognizer confidence is too low to continue without more user input; (4) multiple timeout prompts which the agent produces if the user doesn't say anything. Each of these specifications is affected by the agent' s dialogue strategy. An agent' s dialogue strategy is implemented as a combination of the prompts that are played to the user and the state transitions that the agent makes in response to the user' s utterance. In particular, alternative prompts can be specified for all types of prompts (initial, help, rejection and timeout) to provide alternate dialogue strategies in each state. We implemented alternate strategies for reading messages, for initiative and for summarization. The alternate strategies for reading messages are Read-First, Read-Summarize-Only and Read-Choice-Prompt as in dialogues D1, D2, and D3. The alternate strategies for initiative are a systeminitiative (SI) strategy and a mixed-initiative (MI) strategy. In the SI strategy, the system maintains control of the dialogue and the user must specify one query parameter at a time, as in D4. (D4) A: Hi, Elvis here. You have 5 new and 0 unread messages in your inbox. Say Read, Summarize, or say Help for more options. U: Read. A: Select by Sender, Subject or in order of arrival? U: Sender, A: Which Sender? U: Kim. A: In the messages from Kim, there's 1 message about "Interviewing Antonio". ...... In the MI strategy, the system never tells the user what to do, and the user can take control of the dialogue and specify exactly what they want to do in a single utterance, as in D5. U: Read me my messages from Kim. We also implemented three alternate summarization strategies as responses to a user request to Summarize my messages. The basis for these alternates is ELVIS's decision about which message attributes to mention in the summary. The Summarize-Choice strategy in D6 asks the user to specify which of the relevant attributes to summarize by. (D6) A: Summarize by subject, by sender, or both? U: Subject. A: In your top level inbox, there's 1 message about "Lunch" 1 message about "Interviewing Antonio" .1 message about "Call Me Tomorrow," 1 message about "Evaluation Group Meeting," and 1 message about "Agent Personality:' The Summarize-Both strategy in D7 uses all attributes in the summary: (DT) A: In your top level inbox, from Kim, there's 1 message about "Lunch:' From Michael, there's 1 message about "Evaluation group meeting." From Noah, there's 1 message about "Call Me Tomorrow" and 1 message about "Interviewing Antonio?' And from Owen, there's 1 message about "Agent Personality?' In the Summarize-System strategy in D8, ELVIS summarizes by subject or by sender based on the current context. For instance, if the user is in the top level inbox, ELVIS will summarize by sender, but if the user is situated in a folder containing messages from Noah, ELVIS will summarize by subject, as a summary by sender would provide no new information. (D8) A: In your top level inbox, there's 1 message from Kim, 2 messages from Noah, 1 message from Michael, and 1 message from Owen. Transitions between states are driven by the user' s conversational behavior, such as whether s/he says anything and what s/he says, the semantic interpretation of the user' s utterances, and the settings of the agent' s dialogue strategy parameters. Experimental dialogues were collected via two experiments in which users (AT&T summer interns and MIT graduate students) interacted with ELVIS to complete three representative application tasks that required them to access email messages in three different email inboxes. In the second experiment, users participated in a tutorial dialogue before doing the three tasks. The first experiment varied initiative strategies and the second experiment varied the presentation strategies for reading messages and summarizing folders. In order to have adequate data for learning, the agent must explore the space of strategy combinations and collect enough samples of each combination. In the second experiment, we parameterized the agent so that each user interacted with three different versions of ELVIS, one for each task. These experiments resulted in a corpus of 108 dialogues testing the initiative strategies, and a corpus of 124 dialogues testing the presentation strategies. Each of the three tasks were performed in sequence, and each task consisted of two scenarios. Following PARADISE, the agent and the user had to exchange information about criteria for selecting messages and information within the message body in each scenario. Scenario 1.1 is typical. • 1.1: You are working at home in the morning and plan to go directly to a meeting when you go into work. Kim said she would send you a message telling you where and when the meeting is. Find out the Meeting Time and the Meeting Place. Scenario 1.1 is represented in terms of the attribute value matrix (AVM) in Table 1. Successful completion of a scenario requires that all attributevalues must be exchanged (Walker et al., 1997) The dialogue recordings are used to transcribe the user's utterances to derive performance measures for speech recognition, to check the timing of the interaction, to check whether users barged in on agent utterances (Barge In), and to calculate the elapsed time of the interaction (ET). For each state, the system logs which dialogue strategy the agent selects. In addition, the number of timeout prompts (Timeout Prompts), Recognizer Rejections, and the times the user said Help (Help Requests) are logged. The number of System Turns and the number of User Turns are calculated on the basis of this data. In addition, the recognition result for the user's utterance is extracted from the recognizer and logged. The transcriptions are used in combination with the logged recognition result to calculate a concept accuracy measure for each utteranceJ Mean concept accuracy is then calculated over the whole dialogue and 1For example, the utterance Read my messages from Kim contains two concepts, the read function, and the sender:kim selection criterion. If the system understood only that the user said Read, concept accuracy would be .5. used as a Mean Recognition Score MRS for the dialogue. The web page forms are the basis for calculating Task Success and User Satisfaction measures. Users reported their perceptions as to whether they had completed the task (Comp), 2 and filled in an AVM with the information that they had acquired from the agent, e.g. the values for Email.attl and Email.att2 in Table 1. The AVM matrix supports calculating Task Success objectively by using the Kappa statistic to compare the information in the AVM that the users filled in with an AVM key such as that in Table 1 (Walker et al., 1997). In order to calculate User Satisfaction, users were asked to evaluate the agent's performance with a user satisfaction survey. The data from the survey resulted in user satisfaction values that range from 0 to 33. See (Walker et al., 1998) for more details. Overall, the results showed that users could successfully complete the tasks with all versions of ELVIS. Most users completed each task in about 5 minutes and average ,~ over all subjects and tasks was .82. However, there were differences between strategies; as an example see Table 2 where o~ is a weight on n, ci are the cost functions, which are weighted by wl, and .Af is a Z score normalization function (Walker et al., 1997;Cohen, 1995). The Z score normalization function ensures that, when the weights c~ and wi are solved for, that the magnitude of the weights reflect the magnitude of the contribution of that factor to performance. The performance function is derived through multivariate linear regression with User Satisfaction as the dependent variable and all the other measures as independent variables (Walker et al., 1997). See Table 2. In the ELVIS data, an initial regression over the measures in The basic idea is to apply the performance function to the measures logged for each dialogue Di, thereby replacing a range of measures with a single performance value 19i. Given the performance values Pi, any of a number of automatic learning algorithms can be used to determine which sequence of action choices (dialogue strategies) maximize utility, by using/~ as the utility for the final state of the dialogue Di. Possible algorithms include Genetic Algorithms, Q-learning, TD-Leaming, and Adaptive Dynamic Programming (Russell and Norvig, 1995). Here we use Q-learning to illustrate the method (Watkins, 1989). See (Fromer, 1998) for experiments using alternative algorithms. The utility of doing action a in state Si, U(a, Si) (its Q-value), can be calculated terms of the utility of a successor state S i, by obeying .the following recursive equation: where R(Si) is a reward associated with being in state Si, a is a strategy from a finite set of strategies A that are admissable in state Si, and M~j is the probability of reaching state Sj if strategy a is selected in state Si. In the experiments reported here, the reward associated with each state, R(SI), is zero. 3 In addition, since reliable a priori prediction of a user action in a particular state is not possible (for example the user may say Help or the speech recognizer may fail to understand the user), the state transition model M/~ is estimated from the logged state-strategy history for the dialogue. The utility values can be estimated to within a desired threshold using Value Iteration, which updates the estimate of U(a, Si), based on updated utility estimates for neighboring states, so that the equation above becomes: where Un(a, Si) is the utility estimate for doing a in state Si after n iterations. Value Iteration stops when the difference between Un(a, Si) and Un+l (a, Si) is below a threshold, and utility values have been associated with states where strategy selections were made. After experimenting with various threshholds, we used a threshold of 5% of the performance range of the dialogues. The result of applying Q-learning to ELVIS data for the initiative strategies is illustrated in Figure 1. The figure plots utility estimates for SI and MI over time. It is clear that the SI strategy is better because it has a higher utility: at the end of 108 training sessions (dialogues), the utility of SI is estimated at .249 and the utility of MI is estimated at -0.174. The SI and MI strategies affect the whole dialogue; the presentation strategies apply locally and a See (Fromer, 1998) for experiments in which local rewards are nonzero. can be actived in different states of the dialogue. We examined the variation in a strategy' s utility at each phase of the task, by representing the task as having three phases: no scenarios completed, one scenario completed and both scenarios completed. Table 3 reports utilities for the use of a strategy after one scenario was completed. The policy implied by the utilities at other phases of the task are the same. See (Fromer, 1998) for more detail. The Read-First strategy in D1 has the best performance of the read strategies. This strategy takes the initiative to read a message, which might result in messages being read that the user wasn't interested in. However since the user can barge-in on system utterances, perhaps little is lost by taking the initiative to start reading a message. After 124 training sessions, the best summarize strategy is Summarize-System, which automatically selects which attributes to summarize by, and so does not incur the cost of asking the user to specify these attributes. However, the utilities for the Summarize-Choice strategy have not completely converged after 124 trials. This paper illustrates a novel technique by which an agent can learn to choose an optimal dialogue strategy. We illustrate our technique with ELVIS, an agent that supports access to email by phone, with strategies for initiative, and for reading and sum-marizing messages. We show that ELVIS can learn that the System-Initiative strategy has higher utility than the Mixed-Initiative strategy, that Read-First is the best read strategy, and that Summarize-System is the best summary strategy. Here, our method was illustrated by evaluating strategies for managing initiative and for message presentation. However there are numerous dialogue strategies that an agent might use, e.g. to gather information, handle errors, or manage the dialogue interaction (Chu-Carroll and Carberry, 1995;Danieli and Gerbino, 1995;Hovy, 1993;McKeown, 1985;Moore and Paris, 1989). Previous work in natural language generation has proposed heuristics to determine an agent's choice of dialogue strategy, based on factors such as discourse focus, medium, style, and the content of previous explanations (McKeown, 1985;Moore and Paris, 1989;Maybury, 1991;Hovy, 1993). It should be possible to test experimentally whether an agent can automatically learn these heuristics since the methodology we propose is general, and could be applied to any dialogue strategy choice that an agent might make. Previous work has also proposed that an agent's choice of dialogue strategy can be treated as a stochastic optimization problem (Walker, 1993;Biermann and Long, 1996;Levin and Pieraccini, 1997). However, to our knowledge, these methods have not previously been applied to interactions with real users. The lack of an appropriate performance function has been a critical methodological limitation. We use the PARADISE framework (Walker et al., 1997) to derive an empirically motivated performance function, that combines both subjective user preferences and objective system performance measures into a single function. It would have been impossible to predict a prior{ which dialogue factors influence the usability of a dialogue agent, and to what degree. Our performance equation shows that both dialogue quality and efficiency measures contribute to agent performance, but that dialogue quality measures have a greater influence. Furthermore, in contrast to assuming an a priori model, we use the dialogues from real user-system interactions to provide realistic estimates of M/~, the state transition model used by the learning algorithm. It is impossible to predict a priori the transition frequencies, given the imperfect nature of spoken language understanding, and the unpredictability of user be-havior. The use of this method introduces several open issues. First, the results of the learning algorithm are dependent on the representation of the state space. In many reinforcement learning problems (e.g. backgammon), the state space is pre-defined. In spoken dialogue systems, the system designers construct the state space and decide what state variables need to be monitored. Our initial results suggest that the state representation that the agent uses to interact with the user may not be the optimal state representation for learning. See (Fromer, 1998). Second, in advance of actually running learning experiments, it is not clear how much experience an agent will need to determine which strategy is better. Figure 1 shows that it took no more than 50 dialogue samples for the algorithm to show the differences in convergence trends when learning about initiative strategies. However, it appears that more data is needed to learn to distinguish between the summarization strategies. Third, our experimental data is based on short-term interactions with novice users, but we might expect that users of an email agent would engage in many interactions with the same agent, and that preferences for agent interaction strategies could change over time with user expertise. This means that the performance function might change over time. Finally, the learning algorithm that we report here is an off-line algorithm, i.e. the agent collects a set of dialogues and then decides on an optimal strategy as a result. In contrast, it should be possible for the agent to learn on-line, during the course of a dialogue, if the performance function could be automatically calculated (or approximated). We are exploring these issues in ongoing work. Three different methods are used to collect the measures for applying the PARADISE framework and the data for learning: (1) All of the dialogues are recorded; (2) The dialogue manager logs the agent's dialogue behavior and a number of other measures discussed below; (3) Users fill out web page forms after each task (task success and user satisfaction measures). Measures are in boldface below. n Performance= (a, A/'(,~))-~_,wi* A/'(ci) i=1 2 Yes, No responses are converted to 1,0.

Method for Learning to Optimize Dialogue Strategy Selection