National Institute for Discovery Science: Consequences of Success in SETI by Steven J. Dick

Consequences of Success in SETI:
Lessons from the History of Science

Steven J. Dick

U. S. Naval Observatory, 3450 Massachusetts Avenue, N.W., Washington
D. C. 20392-5100

(From Volume 74, Progress In The Search For Extraterrestrial Life, 1993 Bioastronomy Symposium, Santa Cruz, CA, 16–20 Aug., 1993, of the Conference Series Proceedings by the Astronomical Society of the Pacific, 390 Ashton Ave., San Francisco, CA 94112, USA)

ABSTRACT: The consequences of receipt of a dial tone or information flow from an extraterrestrial civilization are considered in light of historical analogues. It is argued that the history of science offers deeper insights than political history or anthropology, since the contact will be intellectual and not physical. Specific cases of the transmission of knowledge across terrestrial cultures, and of the reception of scientific world views, are offered as analogues to receipt of an extraterrestrial intelligent signal. Particularly apt analogues are the transmission of Greek science to the Latin West via the Arabs in the 12th and 13th centuries, and reception of the Copernican and Darwinian world views. A rich literature awaits those wishing to study the impact of success in SETI based on such analogues.

With the inauguration of NASA's High Resolution Microwave Survey (HRMS) in 1992, the continuing improvements in ongoing programs such as the Planetary Society's META and Berkeley's Project SERENDIP, and the worldwide contemplation of new projects in the Search for Extraterrestrial Intelligence (SETI), it is only prudent that attention should increasingly turn to the societal implications in the event of success in SETI. Many approaches may be taken in discussing such implications. A rich repository of ideas in the literature of science fiction envisions possible consequences of extraterrestrial contact, though much of this is centered on face-to-face rather than radio contact. Hoyle and Elliot (1962), Brown and Zerwick (1968), Gunn (1972) and Sagan (1985) are notable fictional treatments authored by scientists and dealing with the consequences of radio contact.

On the more sober side, a series of three workshops on the Cultural Aspects of SETI (CASETI), sponsored by NASA in 1991-92, set forth broad approaches from the point of view of history, behavioral science, policy and education (Billingham, Heyns and Milne, et al., in press). Here we consider how analogues in history might help to envision and assess the impact following successful detection of a signal from extraterrestrial intelligence.

We recognize at the outset that the societal impact will depend strongly on the circumstances of radio contact. A "dial tone" signal, only giving evidence of intelligence, will be quite different in impact from the decipherment of significant amounts of information. If the latter is achieved, the impact will in turn depend on the nature of the information. Moreover, there are likely to be both short-term and long-term impacts. In this paper we further narrow our focus by considering the long-term impact of the receipt of an intelligent "dial tone" signal (itself a powerful bit of information), or of the flow of information from a deciphered signal, without regard to the information content (which in any case can only multiply speculation). Such a focus, it is hoped, may at least yield a first-order approximation to the general reaction to discovery of intelligent life in the universe. A study of short-term impact, probably dominated by media reaction and political maneuvering in addition to scientific study, requires quite a different analysis, not attempted here.

The consequences of detection of a signal from extraterrestrial intelligence have sometimes been compared to physical contact between cultures on Earth. Readers have been invited to consider Cortez and the Aztecs, Pizarro and the Incas, or Europeans and the American Indians. The European clashes with the Ottoman empire in the 16th and 17th centuries, the British Raj in India, the attempts of Peter the Great at the Westernization of Russia in the 18th century, and Matthew Perry and the opening of Japan in the mid-19th century are other examples taken only from the Western tradition of expansionism. We propose here, however, that the signal obtained from SETI programs is not analogous to physical contact, but rather to intellectual contact and the diffusion of ideas among cultures. This suggests that analogues should be drawn not from political history and anthropology, but from the history of ideas, and in particular the history of science, since the discovery will be a scientific event whose consequences may best be compared to past scientific breakthroughs. As the CASETI participants well realized, even these analogues must not be taken as predictors of action, but only as useful guides to thinking. Analogues "are invoked because so much about SETI is conjectural," the CASETI historians wrote. We follow their principle that "Where ignorance forces conjecture, analogy is a useful (and perhaps the only) guide."

Neither, however, should we underestimate the force of analogy. Scientists, as well as philosophers of science (Giere, 1977; Harre, 1972; Hempel, 1965; Hesse, 1963) recognize analogy as an essential tool of science, both as an aid to thought and more substantially as transferring cognitive content from one scientific problem to another. One might well argue that analogy may also be a useful tool in social and behavioral science, certainly as an aid to thought, and perhaps in transferring principles of human experience between similar events. The underlying assumption for such a suggestion is that while cultural circumstances vary enormously over time and across cultures, human nature does not. At the same time, no analogy is ever perfect; correspondences need not be one-to-one, and any two analogous systems will have differences that may be called "negative analogies" (Hesse, 1967).

In this paper three models from the history of science are offered as analogues to the impact of a SETI detection: the transmission of Greek science to the Latin West via the Arabs in the 12th and 13th centuries; the reception of great cosmological ideas such as the Copernican theory of the 16th century and the "galactocentric revolution" of the early 20th century; and the reception of Darwinian evolution. The first is a model for the consequences of transmission of a broad array of knowledge from one culture to another. The last two provide models for reaction to specific scientific world views similar in nature and scope to the new world view that a successful SETI detection entails. I have called this elsewhere the "biophysical cosmology" (Dick, 1989, 1991).

Assuming that a SETI signal is deciphered and significant information is transmitted, the flow of information between terrestrial civilizations across time is a tantalizing analogue from previous human experience. The transmission of Greek science via the Arabs to the Latin West in the 12th and 13th centuries is an example of what historian Arnold Toynbee called "encounters between civilizations in time" (Toynbee, 1954). Such encounters — which in the case at hand resulted in a renaissance of learning in Europe in the 12th century (Haskins, 1927) - are particularly apt comparisons because they deal with the transmission of knowledge from non-contemporary civilizations across time. Because of the finite speed of microwave communications, non-contemporaneity will hold for extraterrestrial contact in direct proportion to the distance between the communicative civilizations.

One of the best-known episodes of human history is the political fallout from the end of the Roman Empire in the Latin West by 500 AD. Less widely appreciated is that this political dissolution brought with it the loss of Greek learning in science as well as other areas of knowledge. While the flame of knowledge flickered in a few places, only in the 12th century was it recovered, via the Arabs. Scholars, especially in Spain, where the Islamic civilization had been transported in the 8th century, began to translate Greek treatises into Latin, either from the Greek originals or from the Arabic, which by this time had added its own gloss on the ancient knowledge. "First a trickle and eventually a flood," one historian of science recently wrote, the new material "radically altered the intellectual life of the West." Western Europe, which had been struggling to keep the intellectual flame from being extinguished, now had to assimilate a torrent of new ideas (Grant, 1971; Lindberg, 1978, 1992).

While we do not fancy our civilization analogous to the Middle Ages, the torrent of new ideas would be analogous to a significant flow of information from an extraterrestrial civilization to one probably less knowledgeable but eager to learn. The army of translators involved in the recovery of lost learning may find its analogy in the legions of scientists, cryptographers, linguists and others sure to participate in any attempt to decipher an extraterrestrial signal. However, as Lindberg (1978) has pointed out, the medieval translators acted as individuals; there was no central bureau of translations. By contrast, one would hope for some centralization among the many nations likely to be working on the decipherment of a SETI signal.

The result of the newly recovered knowledge is a matter of record. The 13th century - the century of Thomas Aquinas, Albert the Great, and Roger Bacon among other luminaries - was characterized by the attempt of its best scholars to reconcile the new Greek and Arabic knowledge with Christianity. Surely the century following an extraterrestrial signal bearing significant knowledge will also be marked by the attempts of scholars to reconcile terrestrial and extraterrestrial knowledge in many areas — science, religion and the arts. One can only hope that it will not be marked by religious attempts to restrict access to the new knowledge. Even if it is, we note that Aristotelian science was not suppressed forever. It was, however, eventually superseded, leading one to wonder by analogy if terrestrial and extraterrestrial knowledge will be mutually exclusive, coexist with minimal interaction, or blend to become part of a long-sought "objective knowledge" (Popper, 1979).

Many other interesting threads might be followed in this analogy. It is difficult to find in terrestrial history a more appropriate analogy in which the impact of new knowledge was not also accompanied by physical contact or occupation — a complicating element we do not expect from the current radio searches for extraterrestrial intelligence. In summary, in our present model the Greeks are the extraterrestrials, the Arabs the knowledge-bearing medium through which the information is passed, and the medieval translators and commentators those who will bring the new knowledge to the masses. In order to anticipate what might happen then — or to assess what might happen if simply a "dial tone" confirms the extraterrestrial world view - we now turn to the reception of scientific world views in terrestrial history.

More than three decades ago astronomers were already drawing analogies between great changes in cosmological world view and the impact of discovering extraterrestrial intelligence. Shapley (1958) suggested such a discovery would be "The Fourth Adjustment" in mankind's view of itself, after the shift to the geocentric, heliocentric and "galactocentric" world views. The latter was precipitated by Shapley's own work showing that the solar system was at the periphery of our Galaxy. Struve (1961) agreed that astronomy had undergone three great revolutions in the past four centuries: Copernicus' removal of the Earth from the center of the solar system, Shapley's removal of the solar system from the center of the Galaxy, and the revolution embodied in the question "Are we alone in the universe?." Struve seemed to think the latter revolution was already underway, and he may have been right, but surely it will be accelerated by the actual discovery.

What, then, might we learn from the reception of these cosmological world views? Quite different lessons, in fact. The gradual acceptance of the Copernican theory, followed by its triggering of the Scientific Revolution and indeed its impact in all areas of human thought, has now been studied extensively (Beer and Strand, 1975; Kuhn, 1957; Blumenberg, 1987; Stimson, 1972; Westman, 1975). The Copernican theory eventually gave birth to a new physics, caused wrenching controversy in theology, and made the Earth a planet and the planets potential earths. Few other revolutions in history have had such broad, if delayed, consequences.

The galactocentric revolution, on the other hand, is an example of a silent revolution. Astronomers celebrated the discovery; the press routinely reported it; and the general population went about its business as usual despite humanity's slide from the center to the edge of the galaxy (Bok, 1974; Berenzden et al., 1976; Smith, 1982). Berenzden (1975) has noted this dichotomy in the reactions to certain world views. The proof of the galactocentric universe by 1924, he found, "caused almost no discussion whatsoever," in the press, as opposed to Hubble's announcement of the expanding universe five years later. In attempting to explain the difference between silent and noisy revolutions, Berenzden notes that by the mid-1920s revolutions including Darwin, Einstein and Freud (not to mention Copernicanism) had inured the public to marginalization. Moreover, he notes that the basis for the galactocentric conclusion was technical and conceptually non-trivial, lessening its public impact. Finally, and perhaps most importantly, Berenzden emphasized that the galactocentric model did not pose a threat to societal institutions. "When scientific revolutions impinge upon metaphysics or social theory," he wrote, "they are likely to become unusually polemical and possibly unacceptable." These hints, and a voluminous literature on the history and structure of scientific revolutions (Kuhn, 1962, 1970; Cohen, 1985) lead us to conclude that the discovery of extraterrestrial intelligence is more likely to follow the Copernican rather than the galactocentric pattern.

At the same time, a more general lesson may be learned from the reception of world views. Each of these revolutions (indeed all revolutions) follow stages that may be roughly identified as periods of motivation, presentation, elaboration and refinement, exploration of implications, opposition, acceptance, and definitive confirmation or rejection. An examination of Table I shows the specifics of these stages in the development of previous cosmological world views. We note that the geocentric world view held sway for more than 2000 years before its rejection; that a century-and-a-half passed before the heliocentric world view was widely accepted (and almost an equal time interval before stellar parallax proved Earth motion around the Sun); and that the galactocentric world view, by contrast, was accepted very quickly. In many ways, the extraterrestrial, or biophysical, world view has been widely accepted since the mid-18th century, despite the lack of direct evidence. In a sense the stages of elaboration, opposition and exploration of implications have historically already been passed (Crowe, 1986; Dick, 1982). But alas, there has been no empirical evidence of the actual existence of extraterrestrials, nor, of course any final confirmation. When such evidence is at hand, the biophysical world view is likely to repeat the series of stages, at which time the arguments of its historical predecessor - arguments based only on the hypothetical existence of life beyond the Earth — will take on renewed and more immediate meaning. In any event, a closer study of the stages of past world views is sure to illuminate the general path of the putative extraterrestrial world view.

TABLE I Stages in World View Development

Stage	Geocentric	Heliocentric	Galactocentric	Extraterrestrial/ Biophysical
Motivation	motion of planets, anthropocentrism	motion of planets, Neoplatonism geocentric problems	globular cluster, distribution	Copernican theory, cosmic evolution
Presentation Based on Observation	Eudoxus/Aristotle, 4th cent. B.C.	Copernicus, 1543	Shapley, 1917	Kepler (disproven), Lowell (disproven), pulsars (disproven), radio signal?
Elaboration	Ptolemy, et al.	Galileo, Kepler, Newton, et al.	Trumpler, Oort, et al.	range of scientists
Opposition	anti-rationalists	geocentrists, religious	Curtis, et al.	religious, philosophical, scientific
Exploration of Implications Outside Field	anthropocentric religions and philosophies	philosophical, literary, scientific	further proof of non-anthropocentrism	all aspects of human knowledge
General Acceptance	4th cent. B.C.	1700	1930s	widely accepted 1750
Final Confirmation	disproven	1838 (stellar parallax = Earth motion)	1950s (radio maps of Galaxy)	deciphered signal? UFO identified? discovery of ET?

Nor need such analogues be confined to physical world views. To the contrary, because the evolution of life in the universe has an obvious connection with Darwinism — and may even be viewed as an extension of it — the reception of Darwinism may be the best analogue of all in terms of assimilation of world views.

The Darwinian revolution provides a compelling analogue of the trajectory of a biological world view that bears directly on humanity's place in nature. There are, of course, differences in the cognitive status of a theory of evolution by natural selection and a discovery of an artificial signal from outer space. Yet, like the Darwinian theory, the interpretation of an extraterrestrial signal is likely to be ambiguous and debatable, and the diverse reaction to such a signal may therefore be comparable.

The details of the Darwinian revolution are well-known. Indeed, no event in the history of science has been the subject of so much analysis as Darwin's theory and its impact, especially since the centenary of the Origin of Species in 1959 spawned what has aptly been called "the Darwin industry." From the early general historical treatments of Darwinism (Eiseley, 1958; Greene, 1959; Himmelfarb, 1959) to recent historical, philosophical and scientific analyses, the Darwin industry itself provides a model of scholarship likely to be precipitated by a discovery of extraterrestrial intelligence.

These studies show that although there was a long prehistory of the idea of biological evolution (as of extraterrestrial life), the reaction to the Origin of Species — and to the independent work of A. R. Wallace on natural selection — was immediate, widespread, and felt at many levels of society. The first printing of the Origin was sold out in a day, and was followed by many more printings in many languages. In England T. H. Huxley and his allies championed Darwin's cause against all opponents, including Bishop Wilberforce at the infamous BAAS meeting in 1860 at which Huxley announced his preference for the ancestry of an ape rather than the ancestry of a person who, though endowed with intelligence, had Wilberforce's ignorance of science. The debates over Darwinism raged over Europe and the Western world, and eventually over the entire world. Studies have shown how Darwin's theory had distinctive impacts over the short term (Vorzimmer, 1970) and the long term (Bowler, 1989), and among scientists (Hull, 1973), theologians and other segments of the population.

Nor were the battle lines drawn only between broad disciplines such as science and theology. A diversity of opinion existed even within disciplines. Many scientists, while accepting evolution, rejected natural selection, the centerpiece of the Origin. Although this has led some (Bowler, 1992) to the view of a "non-Darwinian revolution," Mayr (1991) has emphasized that Darwinism meant many things to many people but the revolution was Darwinian nonetheless. While Darwinism spurred scientific research and gave birth to biology as a unified science (Smocovitis, 1992), it was eclipsed for many years until the second Darwinian revolution in the 1930s and 1940s incorporated genetics in the "evolutionary synthesis" (Mayr, 1982; Mayr, 1988; Mayr and Provine, 1980). And on the theological side, the debate has never ended. It spawned the Scopes trial in 1925, and is still with us today in the form of "creation science." In a broader sense, Darwin unconsciously spawned aberrant theories like social Darwinism.

Many of these characteristics are likely to be mimicked by the discovery of extraterrestrial intelligence: an immediate strong reaction despite a long prehistory of the idea; the short-term heated controversies; the spur to scientific research punctuated by periods of relative neglect; the diversity of opinion among and within groups; the widespread effect on areas of society that we cannot now predict; and above all, the transformation of the way in which we view our place in nature. Huxley's Man's Place in Nature (1863), in which he discussed man's place among the apes, is likely to be extended to a discussion of humanity's place in the universal chain of being, giving specifics to a long historical tradition (Lovejoy, 1971).

The aptness of the Darwinism analogy is heightened by the fact that Wallace himself already saw a connection between evolution and extraterrestrials in his volume Man's Place in the Universe: The Results of Scientific Research in Relation to the Unity or Plurality of Worlds (1903). Wallace, however, used an anthropocentric cosmology to conclude that the Earth was the only inhabited planet in the universe, and was also the first evolutionist to argue that the complexity of life and the principles of natural selection would never lead to man or intelligence on another planet. This is a view that some evolutionists such as Simpson (1964) and Mayr (1985, 1993) continue to espouse. For our purposes here it matters not whether one accepts Darwinism as an argument for or against extraterrestrial life. What matters is that the validity of Darwinism as an analogy for reaction to the extraterrestrial world view is greatly strengthened by the fact that Darwin's theory applies to the terrestrial evolution of life, while the extraterrestrial world view deals with the cosmic evolution of life. The discovery of extraterrestrial intelligence will surely shed light on the universality of Darwinian principles; conversely, terrestrial Darwinism may become a subset of the extraterrestrial world view. Instead of mankind absorbing the impact of a position at the pinnacle of the apes, it may be forced to deal with its position among civilizations millions of years older.

In this paper we have presented only a bare outline of specific events in the history of science most relevant to understanding the impact of the successful detection of extraterrestrial intelligence. A rich literature in that discipline awaits those interested in further studying the impact of the transmission of knowledge across cultures, as well as in assessing the impact of new scientific world views on culture, in relation to the possible impact of a successful SETI detection. One must always take precautions in using such analogues. Nonetheless, they may well serve not only as useful guides to thinking but also as real, if imperfect, indicators of likely human reaction to future events corresponding to past human experience.

We do not wish to imply that other disciplines may not also be useful in discussing human reaction to the discovery of extraterrestrial intelligence. Anthropology and history may contribute in other ways. For example Finney (1990) uses culture contact to argue cogently that communication between terrestrial and extraterrestrial cultures may be much more difficult than we anticipate — a point that may well be valid. But for the long-term reaction to extraterrestrial intelligence considered as a world view with serious implications for humanity's place in the universe, the history of science offers unparalleled analogues.

As a model for the transmission of broad body of knowledge, the renaissance of the 12th century, and the assimilation of the new knowledge in the 13th and 14th centuries, serves as an optimal terrestrial analogues. As a model for the reception of a new world view, reaction to the Copernican and galactocentric cosmologies offer contrasting models, while the reception of Darwinism - with its clear implications for humanity's place in nature - may be the best model of all. If, indeed, the evolution of extraterrestrial intelligence does occur by Darwinian natural selection, the discovery of life in the universe may be viewed as an extension of the Darwinian revolution; even if it does not, if the mechanism turns out to be different, the reaction to the discovery may be similar. Close scrutiny of detailed studies of these terrestrial analogues might repay substantial dividends for those interested in cultural aspects of SETI.

Whatever model is taken as the best terrestrial analogue, much may be gained from an analysis of the general course of scientific world views. In its broad outlines, the discovery of extraterrestrial intelligence is likely to follow the same general course as have other scientific world views. As Copernicus eventually had his Galileo and Newton, and as Darwin had his Huxley, so will the biophysical world view have its defenders. As Copernicus had his religious and scientific critics and Darwin had his Wilberforce, so will extraterrestrials. The philosophical, literary and scientific turmoil following the 12th century renaissance, and the Copernican and Darwinian world views, is sure to be duplicated. But eventually — if the evidence bears scrutiny - there will be final confirmation that over the long term will overwhelm the skeptics. Surely, history teaches us that the impact of a successful detection of extraterrestrial intelligence will vary with different levels of society, and may be absorbed over a lengthy time period.

This much is predictable from human nature, which has remained largely unchanged over the millennium of analogues discussed here, despite scientific and technological advance. By contrast, we know nothing of extraterrestrial nature or the extent of their knowledge. Therefore, whether the course of the extraterrestrial revolution will bring us, in Arthur C. Clarke's concept, to "Childhood's End," we cannot now say.

As a member of the CASETI workshops, the author acknowledges the stimulating discussions of the CASETI history group, including John Heilbron, Jill Conway, Kent Cullers, Ben Finney, Karl S. Guthke and Ken Keniston, as well as cross-fertilization with the other groups of the workshop.

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Consequences of Success in SETI: Lessons from the History of Science

Consequences of Success in SETI:
Lessons from the History of Science