Life and Intelligence in the Universe

Religion and the Physical Sciences. Kate Grayson Boisvert. Greenwood Guides to Science and Religion. Westport, CT: Greenwood Press, 2008.

No aspect of cosmic evolution has raised a broader range of scientific, philosophical, and religious issues than the possible existence of life and intelligence on other worlds. And none has posed a greater challenge to scientific theory and observation. We have only one sample of life and intelligence to study, no accepted theory of life’s origin, and enormous challenges to observation and communication with other possible inhabited worlds. For all these reasons, scientists have found it impossible so far to assess empirically or agree theoretically about the probability or characteristics of life elsewhere. For the last century a lively debate persisted about whether such life exists, what the philosophical and religious implications would be, and whether searching is worthwhile. Belief and support for search projects waxed and waned but grew stronger in the second half of the century when a handful of passionate proponents established an ongoing search program, arguing that the benefit to humanity could be momentous, both materially and spiritually. The search itself, some claim, has religious overtones, and success would have immense implications for humanity’s self-image and for religious doctrines.

Twentieth-Century Developments

As the century opened, habitable planets were thought by astronomers to be plentiful, and public interest was keen in response to the alleged observation of Martian “canals” by astronomers Giovanni Schiaparelli and Percival Lowell, who saw them as evidence of a superior, peaceful, intelligent race (Basalla 2006, 66, 86-87). A decade later, more accurate observations dispelled the notion, but fictional depictions of Martian life continued to fuel public fascination and deeply impress a generation of future space scientists (Basalla 2006, 9). During the next two decades, however, skepticism grew among scientists, not only as a backlash against the Martian canal fervor but also because of a shift in the dominant view about the solar system’s origin and the possible abundance of planets. In this period, a new “tidal” or close encounter theory gained favor over the earlier nebular hypothesis. As formulated by English physicist and astronomer Jeans, this theory suggested that a passing star could have produced tidal distortions in the sun, causing the ejection of a long stream of hot gas that condensed into planets. Calculating that perhaps only one encounter would occur in 30 billion years, Jeans argued that solar systems and life must, indeed, be very rare (Dick 1998, 74, 76). Jeans’ colleague Eddington echoed this assessment, asserting that nature may have a single purpose—to create million of stars so that just one might “provide a home for her greatest experiment, Man” (Dick 1998, 78-79; Basalla 2006, 127).

Mid-century, the tide dramatically shifted again with new developments in theory, observation, and experimentation in both physical and biological sciences. Criticisms of the tidal theory on dynamical grounds caused its demise in the late 1930s, and in the early 1940s a modified nebular hypothesis gained new acceptance, reviving the idea that planets form as a natural accompaniment to star birth. Around the same time, two independent research projects claimed to have detected planet-sized bodies around two nearby stars, further suggesting that planets might be abundant. Additional support came from the new cosmology, which presented an expanding universe of tens of billions of large galaxies, suggesting that even if planetary systems were relatively rare in our galaxy, their numbers in the universe were still staggering. Finally, studies of the biochemical origin of life also fostered support for its extraterrestrial existence. The experiment by Urey and Miller showed that in a hydrogen-rich and oxygen free “reducing” atmosphere amino acids can be readily synthesized from simple inorganic compounds believed abundant on the primitive Earth and elsewhere in the universe. This lent support to the Oparin-Haldane hypothesis of life’s very natural origin from a primordial broth of prebiotic chemicals and strongly implied that life would easily develop elsewhere as well. Even though such processes were assumed to occur by chance interactions, the enormous time available, then estimated at 2 billion years, made life’s development inevitable. Biologist George Wald summarized the standard conclusion: “Wherever life is possible, given time, it should arise” (Basalla 2006, 130). In his estimate 100,000 Earth-like planets exist in our Galaxy, each one a potential host for living things.

These developments gave rise to what has become the dominant modern conception of the place of life and humanity in the universe, held to this day by the great majority of physical scientists. It strongly reconfirmed the Copernican paradigm, now enlarging its scope to incorporate a much vaster universe and the realm of living beings. It also presented a clear challenge to any religious doctrine that regarded the Earth or its life as unique or special. Astronomer Harlow Shapley, one of the architects and heralds of the new vision, gave a poetic summation:

[Earth and its life are] on the outer fringe of one galaxy in a universe of millions of galaxies. Man becomes peripheral among the billions of stars in his own Milky Way; and according to the revelations of paleontology and geochemistry he is also exposed as a recent, and perhaps an ephemeral manifestation in the unrolling of cosmic time. (Dick 1998, 86)

He further elaborated its implications for extraterrestrial intelligence: “We are a little vain or anthropocentric if we consider ourselves the center of life and the highest being in the universe.” With such a high probability that other intelligent beings inhabit the cosmos and share our aspirations, he remarked, “to deny them this privilege of having philosophers talking about the universe is not fair” (Witham 2003, 11).

Shapley saw deep implications for religion. Once critical of the traditional religious biases of some scientists, he later found “modernist religious people” to be valuable partners in world political causes he cherished, and he also sought to share with them his deep convictions about humanity’s non-privileged place in the modern universe. In 1954 he helped establish a forum dedicated to a “rational, almost scientific, religion”—the Institute on Religion in an Age of Science (IRAS)—where science could “strengthen religion and not upset it.” The dialogue was a valuable “confrontation of religion and science,” although he felt that scientists fared much better and that “theology was in a bad way” (Witham 2003, 10).

Another scientist who explored theological implications of extraterrestrial life at mid-century was the British astrophysicist and cosmologist E. A. Milne. In a lecture on modern cosmology and the Christian idea of God, he asked, “Is it irreverent to suggest that an infinite God could scarcely find the opportunities to enjoy Himself, to exercise His godhead, if a single planet were the sole seat of His activities?” Furthermore, he argued, “there is nothing to prevent each [one] being the seat of a unique process of biological evolution.” For Milne, God did not act all at once to “wind up the world and leave it to itself” but continually guided the evolutionary process in an infinite number of instances in an infinite number of locations. “That is of the essence of Christianity, that God actually intervenes in History” (1952, 152-54).

The early 1960s to the mid-1970s was an expansionary period in the search for extraterrestrial life and intelligence. Microbe testing of Martian soil was planned, radio searches and transmissions initiated, and meetings on the topic held, now attended by origin of life specialists as well as physicists and astronomers. The interdisciplinary field of “exobiology”— now termed “astrobiology”—was born. Several scientists emerged as chief proponents and spokesmen—physicist Philip Morrison and biologically inclined astronomer Carl Sagan, who both coauthored seminal publications, and astronomer Frank Drake, who was the first to conduct a radio search and developed the famous “Drake Equation.” This formula estimated the number of radio-communicating civilizations in the Galaxy by multiplying together several astronomical, biological, and social factors, such as the number of habitable planets, the number that actually support life, the fraction that develop radio communicating intelligence, etc. Though often criticized for being too speculative and imprecise, the equation has remained useful as a concise summary of the important issues in the field and as a focal point for discussion, often elaborated by additional factors. The results, as estimated by the first researchers, ranged between one thousand and one billion, with Sagan later settling on and typically using a figure of one million. Such large estimates greatly encouraged the advocates for contact, and at the close of this period, Drake sent his famous interstellar message, a binary code pictorial representation of the solar system, the human form, and the four nucleotides of DNA (Basalla 2006, chapter 8).

As at all periods, however, the enthusiasm was not universal, and during this time increasing doubts were expressed by some scientists about the probability of the first living forms emerging by chance and of anything like human intelligence evolving elsewhere. A few mathematicians argued that chance interactions could never have led to complex life forms, and the chemist Michael Polanyi claimed that the DNA molecule with all of its information content could not have been synthesized by random processes (Witham 2003, 100). Additional challenges came from the discovery of 3.8-billion-year-old fossilized microorganisms and the emerging possibility of a non-hydrogen rich early atmosphere, suggesting that there had been very much less time—perhaps only 100 million years or less—and possibly much less hospitable conditions for ready synthesis. The “chance plus time” argument for life’s inevitability was beginning to be challenged. Evolutionists such as George Gaylord Simpson and Theodore Dobzhansky argued that human-like species would never evolve twice, given the unpredictable, inventive nature of evolution. Even if other intelligent species had evolved, they would be so different, chances of communication were nil (Dick 1998, 194-95; Basalla 2006, 178-81).

Another development of this period was the revival of theories of an extraterrestrial origin of life, fueled by the problems with earthbound origin theories discussed above and also by new space discoveries. Improved techniques enabled detection of amino acids in meteorites and simpler organics in comets and molecular clouds. Some even claimed to find the remnants of algae-like organisms in meteorites, although the finding was widely disputed. These developments sparked new interest in “panspermia,” an idea first proposed in the early twentieth century by Swedish chemist and physicist Svante Arrhenius, who hypothesized that the pressure of stellar radiation had caused life’s “seeds” to drift from one world to another. The new theories mostly assumed that only complex organics, and not life itself, had an extraterrestrial origin, although there were the following notable exceptions. Studies by Hoyle and Chandra Wickramasinghe led them to believe that amino acids and nucleotides not only formed in interstellar dust clouds but also then developed into living forms on asteroids and comets and came to Earth during the period of early bombardment by those bodies. Past epidemics and periods of rapid proliferation of new life forms, they later argued, might have been caused by bacteria or viruses or new genes from space. Nobelist Crick and biologist Leslie Orgel advanced as a “logical possibility” the even more radical idea of “directed panspermia”—that extraterrestrials had seeded Earth with life via spaceships. While such wildly speculative ideas never widely caught on, the idea that prebiotic chemicals might have an astronomical origin is still seriously considered today (Basalla 2006, 131-32; Dick 1998, 170, 179-86).

During the last thirty years, the search for extraterrestrial life and intelligence has experienced major ups and downs in support from both the scientific community and from the government. The first significant crisis occurred in the late 1970s with the failure of the Viking mission to detect microbes on Mars, continued problems with origin of life theories, and a mounting disbelief in the existence of extraterrestrials. Challenge came from astronomers who raised anew Enrico Fermi’s famous question: “Where are the extraterrestrials?” Since our solar system is so young, the argument went, older civilizations must surely exist, and since interstellar travel is by no means impossible, where are they? Believing that empirical results were the surest way to silence critics, proponents persisted in developing and securing NASA funding for a radio search program called SETI (Search for Extraterrestrial Intelligence) and sustained it through private funds when they lost NASA support for a decade (Basalla 2006, chapter 9; Dick 1998, chapter 7).

From their different perspective, evolutionists have continued to exert an influence on the program, agreeing among themselves about the non-prevalence of human-like aliens but disagreeing as to whether some kind of non-humanlike intelligence might exist beyond the Earth. Paleontolo-gist Stephen Jay Gould argued for the possible evolution of intelligence on other worlds as a phenomenon of “convergence,” whereby numerous pathways can lead to the same function, as with eyes for vision on Earth. Accepting that there was some possibility of intelligence elsewhere, he joined four other evolutionists in 1982 signing a pro-SETI petition. In contrast, biologist Ernst Mayr argued strongly against the possibility, noting the long time it took for intelligence to develop here and the inapplicability of convergence, since intelligence only developed once on Earth (Basalla 2006, 178-85; Dick 1998, 196-97).

Most recently, two opposite trends have emerged. Tantalizing new discoveries have increased the hope of finding life beyond Earth at the same time that new hypotheses from physical science have suggested that Earth may be unique as a bearer of complex life and intelligence. One discovery was the detection of numerous planet-sized bodies circling other stars, and another was the possible finding of fossilized bacteria in a Martian meteorite found in Antarctica. While the latter is now questioned, the success of the former has continued unabated with over 200 extrasolar planets detected to date. Although none have Earth’s mass or distance from its sun, present techniques could not find such planets. Hope for finding life in the solar system also increased with the discovery of liquid environments on the Jovian satellites Europa and Titan. Continued study of “extremophiles”—microorganisms that can live in such inhospitable conditions as extreme heat, cold, salinity, or acidity—was further evidence that life beyond Earth might be more plentiful than previously thought. Encouraged by all these developments and in response to continued public interest, NASA created the Astrobiology Institute in the late 1990s and in 2001 reinstated SETI scientists as one of its teams (Basalla 2006, 172).

In contrast to these hopeful signs were new hypotheses from a few physical scientists that Earth’s complex life and intelligence might be very rare. In their book Rare Earth, geologist Peter Ward and astronomer Donald Brownlee argued that while simple life developed quickly on Earth and is probably common in the universe, complex life and intelligence are not. This is due to the many rare astronomical and geological conditions required to maintain Earth’s stability over the multi-billion year span of time it took complex life and intelligence to develop. Such conditions, they assumed, were the result of chance. In The Privileged Planet astronomer Guillermo Gonzalez and philosopher Jay Richards also analyzed these rare conditions leading to intelligence and further argued that they have also made the Earth a supremely fit location for observing the universe. The simultaneous occurrence of multiple conditions required for both habitability and measurability, they claim, is so improbable that they could never have occurred as a chance fluke of cosmic evolution. While the thrust of their argument is to challenge Copernicanism and make design arguments, and they do not rule out the possibility of alien intelligence, the implication is that it is very unlikely.

At the present time, then, not a single confirmed discovery of life beyond Earth has been made, multiple ideas about life’s origin are being pursued, and views of life’s prevalence range from plentiful to singularly rare. Nevertheless, the last century saw notable progress in the field as physical and biological scientists established interdisciplinary programs to search for both life and intelligence elsewhere and conduct origin of life studies. The notion has also become deeply entrenched in the public imagination with many polls showing that half or more of the general public believes in the existence of some form of extraterrestrial life (Dick 2000, 195). Among origins of life researchers, astronomers, astrobiologists, and no doubt many other scientists, there is widespread acceptance, although certainly not consensus, that life beyond Earth is a natural outgrowth of cosmic evolution, with biological evolution inevitably following chemical evolution in many places in the universe. This acceptance is based, more than anything, on philosophical assumptions.

Philosophical and Religious Implications Seen by Scientists

As with the anthropic principle and all of cosmic evolution, the possibility of life and intelligence throughout the cosmos raises philosophical and religious issues that underlie all questions of origin and the relation of humanity to the universe and to God. These issues are the role of chance, necessity, and design in originating life and evolving it to consciousness and the cosmic significance and spiritual status of the human being. Related to the latter are issues of a more religious nature—the effect that an abundance or absence of other intelligence-bearing worlds would have on religious doctrines and concepts of God and the notion that searching for extraterrestrial intelligence may itself be a form of religious quest.

Chance, Necessity, and Design In Life’s Origin

Scientists today, for the most part, no longer debate whether life had a natural versus miraculous origin, at least in public discussions. Mainstream discourse now revolves around the more philosophical notions of chance and necessity. Although all scientists working in the field acknowledge the role of both chance and necessity in life’s origin and evolution, many emphasize the dominance of one over the other. Others argue for a weak determinism, in which supplementary laws of self-organization and rules of information theory now being developed would play a major role. In almost all of these philosophical positions, life and intelligence might be common, the exception being chance causation by a rare contingent event. A few, even when speaking as scientists, argue for design—either by a traditional God or some unspecified “superintellect.” The implication of this position for life’s existence beyond Earth is indeterminate.

Life by Chance

The position that life originated as a rare chance occurrence has been held by many physical scientists and biologists over the last century but was most famously argued by French Nobel biologist Jacques Monod in his book Chance and Necessity (1972). He wrote:

[Life was] the product of an enormous lottery presided over by natural selection, blindly picking the rare winners from among numbers drawn at utter random… The universe was not pregnant with life, nor the biosphere with man. Our number came up in the Monte Carlo game. (Dick 1996, 382)

He estimated that life’s chance of originating “was virtually zero”—a view supported by various researchers’ calculations of the time required for random molecular shuffling to produce simple proteins, RNA or a bacterium. These estimates exceeded the time available in Earth’s history by factors of several hundred to several hundreds of millions—staggeringly improbable numbers that bolstered Monod’s idea that life’s cause was a freakish accident. Not all researchers doing these calculations drew the same conclusion. French scientist Lecomte du Nouy and astronomer Hoyle invoked design by God or a superintellect, and physicist Harold Morowitz and biochemist Robert Shapiro were led to explore different mechanisms for molecular biogenesis (Dick 1998, 187-89). Nevertheless, a large number of life scientists came to agree that life’s origin was driven by chance and was dauntingly improbable—at least if caused by random molecular assembly. Mayr summarizes well this view and its clear implications for extraterrestrial life:

A full realization of the near impossibility of an origin of life brings home the point how improbable this event was. This is why so many biologists believe that the origin of life was a unique event. The chance that this improbable phenomenon could have occurred several times is exceedingly small, no matter how many millions of planets in the universe. (Dick 1998, 169)

The “life by chance” hypothesis posits further that even if simple life could readily form, the likelihood of its evolution into human-like intelligence, or perhaps any intelligence at all, is virtually nil. Humans are the product of a staggering number of distinct variations brought about by chance and selected by whatever environment an organism happens to inhabit. As expressed at the dawn of the last century by evolution’s co-founder, Alfred Russell Wallace, “The total chances against the evolution of man, or an equivalent moral and intellectual being, in any other planet, through the known laws of evolution, will be represented by a hundred million of millions to one” (Dick 1998, 193). Two decades later paleontologist W. D. Matthew agreed with Wallace’s assessment and his view that such estimates almost surely excluded extraterrestrial intelligence. Even if it did arise elsewhere by a fluke, such intelligence would most assuredly neither resemble ours nor be accessible to us. Mid-century anthropologist Loren Eiseley chimed in, “Of men elsewhere, and beyond, there will be none forever… Every creature alive is the product of a unique history. The statistical probability of its precise reduplication on another planet is so small as to be meaningless” (Dick 1998, 194). In the 1960s and 1970s Simpson and Dobzhansky both emphasized the extreme unlikelihood and nonrepeatability of humanity’s emergence, while Mayr argued that any kind of intelligence was unlikely. Gould later joined the chorus, calling evolution

…a staggeringly improbable series of events, sensible enough in retrospect and subject to rigorous explanation, but utterly unpredictable and quite unrepeatable. Wind back the tape of life to the early days of the Burgess Shale; let it play again from an identical starting point, and the chance becomes vanishingly small that anything like human intelligence would grace the reply. (Dick 1996, 394)

A corollary of the chance hypothesis is that the process of evolution can in no way be interpreted as progressive or advancing. Because each individual change happens purely by “chance caught on the wing,” as Monod put it, the fact that more complex and even conscious beings developed from simpler ones is itself pure accident. Gould was especially forceful on this point: “Progress is a noxious, culturally embedded, untestable, nonoperational, intractable idea that must be replaced if we wish to understand the patterns of history” (Davies 1995, 76).

Life by Necessity

In sharp contrast to the chance hypothesis is the position that life has developed as a necessary outcome of the working of known physical laws, wherever conditions were suitable. Life and mind were not a fluke; they were built into the fabric of the universe. Chance still plays a part, but the odds are overwhelmingly in favor of life’s formation. An early twentieth century argument for necessity came from biochemist Leonard Troland, who proposed an enzyme theory for life’s genesis:

The striking fact that the enzyme theory… necessitates the production of only a single molecule of the original catalyst, renders the objection of improbability almost absurd… and when one of these enzymes first appeared, bare of all body, in the aboriginal seas it followed as a consequence of its characteristic regulative nature that the phenomenon of life came too. (Dick 1996, 380)

Around mid-century British Astronomer Royal Sir Harold Spencer Jones and organic chemist Melvin Calvin, an early exobiologist, both argued for life’s inevitable appearance, given the proper conditions, Calvin going so far as to say that estimating the probability of cell life in the universe required only a knowledge of the number of planets with Earth-like conditions. The codeveloper of the “primordial broth” hypothesis for life’s origin, Russian biochemist A. I. Oparin, concluded in 1975:

There is every reason now to see in the origin of life not a “happy accident” but a completely regular phenomenon, an inherent component of the total evolutionary development of our planet. The search for life beyond Earth is thus only a part of the more general question which confronts science, of the origin of life in the universe. (Dick 1998, 269)

In recent years Belgian biochemist Christian de Duve has been a strong voice for biological determinism. To say that the universe was not pregnant with life, he argues, is to invoke miracles, but modern biology demonstrates that divine intervention was not required. Here he is noting the philosophical similarity of origin by chance and origin by divine act—they are both contingent events—and rejecting them both. For him,

Life and mind most likely developed through purely natural events rendered possible by the prevailing physical-chemical conditions or perhaps even imposed by these conditions… The “pregnancy” that was erroneously negated by Monod is in fact the outcome of very special features built into the natural structure of the universe. (de Duve 2000, 11-12)

Rejecting the “gospel of contingency” by which humanity is a “meaningless outcome of chance events in a pointless universe,” de Duve sees our emergence as a “watershed” rich in significance. A species has now developed that is beginning to discern the “reality behind the appearances”—not only the nature and history of the physical universe, but also such abstractions as “truth, beauty, goodness and love… the closest we can get with our feeble means to the ultimate reality to which many give the name of God.” Superior beings of the future will no doubt have clearer vision of these realities, but for him “the glimpses we are afforded already are immensely rewarding” (de Duve 2000, 12-13). In his view the universe, through us, is growing toward greater consciousness of an ultimate spiritual reality. Although superior aliens may exist today and the possibility should certainly be included in our cosmology, according to de Duve they in no way detract from the meaningfulness of what has happened here.

Another argument for the significance of emerging consciousness comes from Davies. In his book Are We Alone: Philosophical Implications of the Discovery of Extraterrestrial Life, he points to the remarkable fact that the organ of greatest complexity in the universe, the human brain, is capable of grasping the laws that govern the simplest level of matter. This “deep and still mysterious… cosmic connection… between minds that can do mathematics and the underlying laws of nature that produce them” surely suggests how fundamental and prevalent consciousness must be. To find extraterrestrial intelligence would be a confirmation of this essential role of mind in the cosmos and of the progressive nature of the evolutionary process (Davies 1995, 127-29).

The idea of evolutionary advancement is a common feature of deterministic thinking. In contrast to the firm denial of directionality by most evolutionists, a few biologists argue that the development from simple to complex to conscious life is clearly a “ladder of progress.” Christian de Duve holds that while individual variations are random, there is nevertheless a general, inherently predetermined direction toward greater complexity and eventual consciousness, an idea supported by the occurrence of evolutionary convergence, according to British paleobiologist Simon Conway Morris. In convergence, independent genetic pathways invent similar functions in widely different creatures, such as wings for flight or eyes for vision, or animals filling similar niches in different locales, such as placental and marsupial mammals. In the same way, Conway Morris argues, wherever life arises, a humanlike niche will eventually evolve, and on other planets intelligent beings would even resemble us in appearance (Davies 2003).

Philosophically, exobiologists, most of them biochemists or physical scientists, subscribe to a version of necessity. Life is inevitable not so much because it is intrinsic to physical laws but rather because of the enormous temporal and spatial range where pure chance can operate. Astronomer and science historian Dick summarizes their position: “Given enough time or space, or a simple enough entity, or the need for only a single first molecule, exobiologists could argue that an event governed by chance was transformed into necessity when the laboratory was the immense, and immensely old, universe” (1998, 187). Over the past half century they have persisted in this view, extending it to include the inevitable evolution of intelligence. Nearly all exobiologists would probably agree with Sagan’s assessment:

Once life has started in a relatively benign environment and billions of years of evolutionary time are available, the expectation of many of us is that intelligent beings would develop. The evolutionary path would, of course, be different from that taken on Earth. The precise sequence of events that have taken place here… have probably not occurred in precisely the same way anywhere else in the entire universe. But there should be many functionally equivalent pathways to a similar end result. (Dick 1996, 397)

Some physicists and exobiologists, however, went further than Sagan, arguing that even human-like intelligence would necessarily arise. Such prominent physicists as Nobel laureates Glashow and Weinberg, as well as astronomer Drake, all asserted that “humanoids” on other worlds would have “alien mathematics and science… essentially like ours,” and Drake speculated that even in their physical form they “won’t be too much different from us” (Basalla 2006, 176-177, 198).

Commentators have noted diverse philosophical implications in the positions of exobiologists, among them anthropomorphism, adherence to the universality of physical law, and Copernicanism applied in contradictory ways. Historian Basalla (2006, 199) sees belief in the necessary development of human intelligence as clear anthropomorphic provincialism—even labeling Sagan an “electronic chauvinist” for assuming radio communicating ability in aliens. Dick sees it as stemming from a normal assumption physical scientists hold—that all laws, including biological ones, are universal and bound to produce the same result everywhere. In fact, Dick identifies the quest for a universal biology as a major part of all extraterrestrial life research—even though it is not a goal shared by most of the biological community (1998, 192). For Gonzalez and Richards, exo-biologists’ mixture of necessity and chance amounts to a philosophical contradiction, an “uneasy amalgam,” well illustrated by a statement of astrobiologist and geologist Bruce Jakosky:

Finding non-terrestrial life would be the final act in the change in our view of how life on earth fits into the larger perspective of the universe. We would have to realize that life on earth was not a special occurrence, that the universe and all of the events within it were natural consequences of physical and chemical laws, and that humans are the result of a long series of random events. (Gonzalez and Richards 2004, 411n)

Thus, two seemingly opposite ideas—that life is natural and common but is still a chance occurrence—are both drawn from the Copernican assumption that Earth life is in no way special. For Gonzalez and Richards, both design advocates, this contradiction simply argues against Copernicanism. In their defense, exobiologists would probably acknowledge the difficulty of philosophical resolution and urge action on the only path promising sure solution—empiricism.

Life by Self-Organization—Weak Determinism

A middle position between chance and determinism, called by some “weak determinism,” has arisen in recent years from theories of self-organization and information science. It posits that life arises with a high probability, not because it is “written into the laws of physics,” but because matter and energy have a natural inclination to “self-organize and self-complexify,” according to principles that are supplemental to but consistent with ordinary physical law (Davies 2000, 18). Study of chaotic systems has demonstrated that self-organization can occur when new energy input forces a system to the “edge of chaos” and away from equilibrium, and it then reacts by unexpectedly and quickly developing greater complexity and order. At the chemical level, certain kinds of self-organizing, interconnecting cycles, called “hypercycles” were found by chemist Manfred Eigen to produce greater complexity much more quickly than simple random molecular interaction. He also found that in “autocatalytic cycles” a system of organic molecules can reach a minimum level of complexity to trigger their own creation in a “self-reinforcing loop” (Davies 1995, 34, 79). Such processes seem to increase greatly the probability that living molecules could form in the short time available in Earth’s history. Biophysicist Stuart Kauffman has applied these ideas to both the origin and evolution of life, offering an alternative or supplemental theory to neo-Darwinism. He proposed that Eigen’s integrated cycles attained some degree of advancement before nucleic acids appeared; when DNA and RNA developed, they simply took command of a preexisting order. With regard to evolution, he argued that the inherent propensity of complex systems to freely create new levels of order is an additional and perhaps more powerful force for change beyond Darwinian natural selection. Nature selects from among systems where spontaneous increase in complexity has already occurred and thus “moulds an already existing biological order… As these forces tangle and vie in coevolving populations, so selection tends to drive the system towards the edge of chaos, where change and adaptation are most efficient.” In this way, Kauffman suggests, something like a “law of increasing complexity” may supplement the known laws of nature (Davies 1995, 78-79).

Concepts of information theory appear to be fruitful and perhaps crucial in forging this middle path between the extremes of pure chance and strong determinism, since living matter, with its structure and function encoded in genetic data, is essentially “an information processing and propagating system” (Davies 2000, 18). Biogenesis and evolution in this context are seen not as questions of how some “exotic chemistry” works but of how biological information originates and develops greater and greater functional complexity. In information terms the structure and function of a macromolecule such as DNA correspond to the “syntax” (the defined sequence of base pairs) and the “semantics” (the meaning or function assigned to the sequence pattern). To pose the question of how life originates and evolves is, then, to ask how each of these aspects arises—first, how macromolecules with biologically useful base sequences are selected from an enormous number of structurally equivalent ones and second, how particular functions or “meaning” are actually assigned to sequence patterns.

The hypothesis of “strong” determinism is ruled out when concepts of information theory are applied to the problem, according to physicist Davies and biophysicist-philosopher Bernd-Olaf Kuppers. If strong determinism held, then there would have to be a physical explanation of how biological macromolecules develop their complex, random, and highly specified sequences that have meaning and function in an organism. Physical law can produce randomness, and self-organization can even select biologically meaningful sequences from among many possible random ones, but no physical law can predict or determine what the sequence will be—that is, what the actual information content is. As algorithmic information theory expresses it, simple physical law, which has low information content, cannot create richer, more complex information than it possesses itself, so the laws of physics and chemistry could not themselves “inject the complexity necessary for a structure” (Davies 2000, 21). The information content of a macromolecule—the “message” in the medium—can only come from unique historical interactions of a biological entity and its environment, which are not expressible in a general law. Darwinian processes can provide both the randomness and functional complexity but are only known to operate on something already living.

Although information science certainly exposes the limitations of strong determinism, there is promise that further developments will support a weaker determinism for biogenesis. New information laws may be discovered that can generate information-rich molecules—actually creating information rather than just moving it around. As Eigen expressed it, “Our task is to find an algorithm, a natural law that leads to the origin of information” (Davies 2000, 24). Some scientists call such ideas mysticism, but others regard such an accusation as unjustified since information theory is still being developed. Better understanding of information “dynamics”—how information flows, relates to the movement of physical matter and energy and connects the parts of a system to the whole—may yet provide clues. Davies speculates that some new principle related to quantum computation may be found that will supplement and expand known laws of local dynamics. Kuppers focuses on the possibility that the origin and development of informational blueprints may be explained by a “general theory of historicity” but concedes that the many small details of historical interactions over time can never be explained by law, since they contain so many “bifurcation points governed by chance” (2000, 42),

Yet another version of weak determinism is a simple extension of Darwinism. It suggests that Darwinian process may have operated even at the prebiotic level on a simple random replicator, which formed by chance. In this “Darwinism all the way down” scenario, variation and natural selection increased both structural and functional complexity of the replicating molecule until nucleic acids and proteins emerged and achieved dominance (Davies 2000, 22). The dilemma is that a replicating molecule complex and large enough to be such a prototype has to emerge by chance, and at the present time, that chance is estimated to be very small. Thus, the genesis of the original information-carrying molecule is still problematic. Kuppers makes a similar point in emphasizing that even in the self-organization scenario explanation of information blueprints has to start from earlier ones, which must simply be posited like initial conditions, so that pursuing their ultimate origin is to fall into an endless “regression cycle” and reach a limit to knowledge. For him, the whole issue is then “open to metaphysical speculation” in the same way that questions of the origin of the universe are (2000, 43).

Life by Design

One last but important philosophical position is causation by design. It is noteworthy that design arguments have traditionally appeared far less in scientific discussions of biogenesis than in speculations about the origin of the universe itself. This is perhaps understandable since the genesis of the cosmos involves more all-encompassing questions of origin—the very beginning of matter and energy themselves and the laws which govern them whereas biogenesis presumably occurred in an already existing material universe. Furthermore, explanations invoking design by God are usually scrupulously avoided, vulnerable as they are to being overturned when natural causes emerge. Nevertheless, design arguments for life’s origin have been offered over the years by a number of scientists, with increasingly varied interpretation of the concept, and more recently they have become the core focus of the Intelligent Design (ID) movement.

In the first half of the twentieth century two influential scientists were among those presenting arguments for life’s purposive or divine origin. Wallace, a key figure in evolutionary thought, invoked the notion of purpose in his 1903 book Man’s Place in the Universe to explain the unlikely appearance of man in the cosmos.

Our position in the material universe is special and probably unique, and… lend[s] support to the view… that the supreme end and purpose of this vast universe was the production and development of the living soul in the perishable body of man. (Dick 1998, 22)

At mid-century du Nouy went further in interpreting life’s tiny chance of appearing. His much acclaimed 1947 book Human Destiny presented calculations of the staggeringly improbable time proteins would take to form by chance but then concluded that probability arguments were not applicable in biology. For him, the findings of science “lead inevitably to God” (Dick 1998, 188).

In the latter part of the twentieth century many scientists continued to propose or believe in design by a purposive creator God, as envisioned above, while others began to interpret design in broader terms, as related to concepts of emergence or the product of an unspecified “intelligence” or “superintelligence.” In his book By Design journalist Larry Witham illustrates the variety of design conceptions that emerged among scientists as theories of biogenesis involving random molecular shuffling over immense time periods began to fail. Biochemist Edward Pelzer, a research scientist interested in evangelical faith and traditional design by God, saw no conflict between science and religion, commenting, “As long as God is the first cause, the mechanism wasn’t important” (Witham 2003, 104). With so many approaches and so little evidence, Pelzer feels that one must simply decide between life’s deliberate creation or natural emergence and for him “the idea that it was purposely designed is becoming ever more apparent” (Witham 2003, 112). Pelzer is exemplary of a large number of scientists who profess firm Christian belief but also adhere firmly to the integrity of the scientific process as practiced by mainstream science.

A different journey—toward softer design views—was followed by the biophysicist Morowitz, who moved from “hard-nosed reductionist” to “mystic scientist” through his pioneering work in applying information theory to simple biological systems. He later labeled as “hubris” his early attempts to calculate all the information and assembly time for the parts of a cell. When he found the assembly time so improbably long as to move the question “outside of science,” creationists were pleased, but he was led to a different realization—that life’s origin needed a significant input of energy that provided new information, something like the “negentropy” conceived by quantum physicist Schrödinger in his famous book What Is Life? These explorations led him into the developing fields of chaos, complexity, and emergence theories, which he feels have “changed science at a deeply epistemological level.” The old mechanistic adding up of parts was inadequate in the face of the “combinatorily explosive” character of living systems, whose game-like processes enhance what works and eliminate what is not useful, giving rise to new and unpredictable emergent properties. Morowitz sees this as a form of design that has no Designer. When queried about his beliefs, he said, “I’m a pantheist in the tradition of Spinoza… I do think of the universe and the divine as being somehow the same or overlapping.” Morowitz is clear, however, as is Pelzer, in distinguishing when he is speculating about religious implications of his work and when he is conducting research as a deterministic scientist (Witham 2003, 108-10).

Perhaps the best known design advocates working today are scientists and philosophers associated with the ID movement, whose core argument is that the complexity of biological forms cannot be accounted for by natural causes and must be explained as the product of intelligence. While most scientists clearly label their design views as personal belief or philosophical speculation, ID advocates present them within the framework of science itself, thus challenging its methodological assumptions.

Two prominent ID proponents, biochemist Michael Behe and philosopher-mathematician William Dembski, both focus on complexity as evidence for design. For Behe, evolution has occurred, but the “irreducible complexity” of numerous cellular structures and processes with finely tuned, interdependent features could never have developed by the gradual, one-at-a-time changes of Darwinian process but had to have been designed by an interventionist intelligence. In his book No Free Lunch: Why Specified Complexity Cannot Be Purchased without Intelligence, Dembski posits three conditions that test for design—contingency, complexity, and specificity. An event or process is contingent if produced by both law and chance, complex if produced by more steps than cosmic time and available particles allow, and specified if possessing a “detachable” pattern—one that can be recognized independently from the event or process. Dembski argues that such evidence for design explains natural phenomena more adequately than law or chance and also better than self-organization processes, which fail because they produce repetitive patterns instead of the nonrepetitive, information-rich ones living organisms possess. In applying Dembski’s design test to the appearance of intelligence, Gonzales and Richards claim that the correlation of Earth’s fitness for developing intelligence with its supreme suitability for scientific discovery is such a specified pattern that reveals intelligent design. However, they follow other ID proponents in making no claim about who or what the “designer” is.

British astrophysicist Hoyle, on the other hand, is quite willing to offer speculation about the nature of the designer. His springboard for design arguments are the many anthropic coincidences in physical laws that allow life to evolve and which seemed to him too contrived to have arisen by chance-driven physical processes. Some “superintellect” must have been at work. In The Intelligent Universe he argues that the extraterrestrial microorganisms that seeded life on Earth were the handiwork of advanced intelligent beings—craftsmen similar in concept to Plato’s Demiurge. Just as the Demiurge was directed by a higher power—The Good—so Hoyle’s advanced beings operate under the direction of a “superintelligence” abiding in an eternal realm (Davies 1995, 136-37).

As these various positions have shown, scientists’ philosophical debates about life’s origin and cosmic prevalence present a more complex picture than previous debates centering on the simpler polarity of nature versus miracles. Debates today revolve primarily around the concepts of contingency and necessity, but these terms are not uniquely defined. Contingency suggests two very different possibilities—origin by chance and origin by design, and both positions appear to have strengthened in recent decades. Similarly, necessity relates to both strong and weak forms of determinism and even to exobiologists’ “pure chance” operating over long enough times. Design positions themselves have proliferated into a number of varieties from the pure contingency of interventionist divine action to the potentially more law-like “design” implied by complexity and emergence theories.

The relation of these various positions to belief in God has also grown somewhat more complicated. Paul Davies argues that while there is a general correspondence between atheism and seeing life’s origin as a “freak accident,” and also between determinism and belief in “meaning, purpose, and design in nature” (Davies 2000, 26-27), these categories are not rigid. He writes, “It’s perfectly possible to be an atheist and believe that life is built ingeniously into the nature of the universe. It’s also possible to be a theist and suppose that God engineered just one planet with life, with or without the help of miracles” (Davies 2003). All of these positions, however, have clear implications for the cosmic status of humanity.

Extraterrestrial Intelligence, Human Significance, and God

Scientists voice a very wide range of views as to how alone, unique, and advanced humans are in the cosmos and what religious significance these possibilities hold. Their views no doubt come from many influences—from personal religious belief or lack thereof to modes of thought inherent in particular scientific disciplines.

Are We Alone?

The idea that humans are solitary inhabitants of the cosmos is a view shared by scientists at opposite ends of the religious spectrum. Both agree that the evolution of intelligence is unlikely in the extreme, but their interpretations could not diverge more. For Monod, the improbability makes intelligent beings a complete fluke and denotes nothing at all about purpose or action by God. His following well-known statement clearly reveals his atheism: “The ancient covenant is in pieces: man at last knows that he is alone in the unfeeling immensity of the universe, out of which he has emerged only by chance. Neither his destiny nor his duty have been written down” (1972, 167). In his footsteps follow many evolutionary biologists and current spokesmen for atheistic evolution. For Wallace, on the other hand, humans are probably alone because God created us so as the universe’s “supreme end and purpose,” and he may have had no need of other intelligent beings to accomplish his aims (Dick 1998, 193). Biologist Conway Morris’ view is clear from the subtitle of his 2003 book: “Inevitable Humans in a Lonely Universe.” He holds that evolution’s convergence on human intelligence only happened here but is part of a universal plan directed by a “lord of all creation,” as Basalla expresses it (2006, 185). In a perspective similar to Wallace’s, but only hinting at God, Gonzalez and Richards suggest that searching for extraterrestrial signals may be missing a grander truth:

Perhaps we have also been staring past a cosmic signal far more significant than any mere sequence of numbers, a signal revealing a universe so skillfully crafted for life and discovery that it seems to whisper of an extra-terrestrial intelligence immeasurably more vast, more ancient, and more magnificent than anything we’ve been willing to expect or imagine. (Gonzalez and Richards 2004, 335)

As discussed earlier, most physical scientists and exobiologists, both theists and atheists, took the opposite view that extraterrestrial life and intelligence are abundant. For theist Milne an “infinite God” can express his “godhead” far better on an infinitude of planets (1952, 152-54). From a very different religious perspective, Shapley viewed the highly probable abundance of life as an obvious extension of the Copernican paradigm and evidence for our unimportance. Earth’s relegation to the outskirts of one galaxy among millions (now billions) made man “peripheral” too. Today historian Dick asserts that most astronomers and origin of life researchers accept life’s cosmic abundance as the most likely scenario and “the working hypothesis of those in the growing hybrid fields of bioastronomy and astrobiology” (2000, 191).

Are We Unique?

But are we unique among our cosmic cohabitants? A number of highly respected physicists and astronomers and a small minority of biologists hold that we are not—extraterrestrials must resemble us—but the majority of biologists disagree. Physicists such as Weinberg and Glashow emphasize similarity in terms of mental capacity and ability to perceive the same universal physical laws, while others claim physical similarity. Drake writes, “They won’t be too much different from us… [A] large fraction will have such an anatomy that if you saw them from a distance of a hundred yards in the twilight you might think they were human” (Basalla 2006, 198). Biologist Robert Bieri agrees that “they will look an awful lot like us” (Basalla 2006, 184). Primack reports the general thinking that intelligent aliens are probably our size, which is optimal for complexity and fast thinking, and may possibly share our fractal circulatory system, rates of energy use, and even lifespans (Primack and Abrams 2006, 224-28). Many biologists, on the other hand, argue for uniqueness on the grounds that the many unpredictable historical steps leading to intelligence could never be duplicated. Eisley gives poetic expression to the special aloneness that uniqueness carries:

Nowhere in all space or on a thousand worlds, will there be men to share our loneliness. There may be wisdom; there may be power, somewhere across space great instruments, handled by strange, manipulative organs, may stare vainly at our floating cloud wrack, their owners yearning as we yearn. Nevertheless, in the nature of life and in the principles of evolution we have had our answer. (Dick 1998, 169)

Exobiologists and SETI astronomers generally believe that most aliens are physically different from humans but intellectually and technologically superior. This follows simply from the fact that humans are a young species in the universe; others must be more advanced. Furthermore, to be plentiful enough to afford us a chance of detecting them, they must be very long-lived. According to SETI astronomer Jill Tarter, “For one of the nearest 1,000 solar-type stars in our galaxy to host another technology, the average longevity L must be measured in tens of millions of years.” To live so long, such societies must have greater wisdom, knowledge, and social stability than ours. They “either never had, or have outgrown, organized religion,” which Tarter sees as a source of so much conflict on Earth (Dick 2000, 145). Drake speculated on another advanced trait—immortality, which aliens achieved by curing all disease. For physicist Jastrow alien scientists achieved immortality by figuring out “the secrets of the brain” and “uniting mind with machine” (Basalla 2006, 13, 160-61). Sagan conjectured that intelligent extraterrestrials have experienced and solved Earth-type social and environmental problems and have established a communication network throughout the Galaxy to spread their knowledge. Sagan’s fictional alien in his book Contact spoke volumes about his hope for what they are like: masters of galactic travel, loving and concerned mentors, and immortals with spiritual, or at least magical, powers.

Are We Special?

Clearly, in such a universe teeming with advanced extraterrestrials, humans have no special status; in fact they have an inferior one. Shapley expressed it well in his comment about our vanity and anthropocentrism in considering ourselves the center of life and the highest being in the universe (Witham 2003, 11). SETI researchers agree that humanity lacks privilege, not only in spatial position but also in technology, knowledge, and probably wisdom. For those believing in life’s cosmic abundance, only religious faith seems to temper this view, as Milne’s example demonstrated. For him, an infinite number of inhabited worlds did not make our world less special in any way; in fact, Christ’s incarnation here may imply just the opposite. In this sense, theists supporting life’s abundance share a strong belief with theists or design advocates who argue that we may be alone: Earth’s location and humanity itself may indeed have a very special status.

Religious Implications of Search and Discovery

Religious Dimensions of the Search

When SETI researchers wax eloquent about the messianic promise of wise, immortal beings from beyond Earth, an obvious question arises: Is their search at heart a “quasi-religious quest”? Does the same religious strand that inspired medieval belief in supernatural angels now inspire some scientists to postulate natural immortal guardians in the heavens? Many commentators have said yes. Basalla argues that old religious and philosophical ideas about superior celestial beings continue to lie beneath current scientific investigation, unacknowledged for the most part by scientists themselves, who mostly profess atheism. These notions became part of modern science, according to one historian, when Western humanity first faced the lifeless emptiness of the Copernican-Newtonian universe and created rational superior beings to fill the void. The ideas persist, according to one psychologist, because yearnings for heavenly beings have deep emotional roots in the human being (Basalla 2006, 12-14). At the present time, speculates historian Dick, SETI may be a current example of what he calls a “universal religion… the never-ending search of each civilization for others more superior than itself.” As such, SETI is “science in search of religion” (Dick 2000, 205).

Davies agrees that the current scientific search for extraterrestrials is “part of a long-standing religious quest,” providing for some a larger framework for meaning in our lives and filling the void left by the decline of traditional religions (1995, 138). He identifies quasi-religious themes in the speculative writings of both Sagan and Hoyle. In Sagan’s Contact, aliens share with a chosen human special knowledge about the universe, hinting at a great intelligent design hidden in its structure. In so doing, they act as angelic-type intermediaries between humans and some overarching, all-knowing presence. Aliens are a kind of “halfway house” to God in Hoyle’s The Intelligent Universe, where two levels of advanced beings are described: cosmic engineers who arranged conditions for life’s development on Earth and a much greater superintelligence who directs them from some timeless realm. Davies describes the obvious religious appeal of this idea:

This powerful theme of alien beings acting as a conduit to the Ultimate… touches a deep chord in the human psyche. The attraction seems to be that by contacting superior beings in the sky, humans will be given access to privileged knowledge, and that the resulting broadening of our horizons will in some sense bring us a step closer to God. (Davies 1995, 137-38)

For Davies, the religious streak is natural, given that theology helped give birth to science and elements of a theological world view are still accepted by working scientists, no matter what their beliefs are about God or extraterrestrial life. Although in current discourse a clear division exists between religious and scientific perspectives, for Davies “this separation is only skin deep” (1995, 138).

A few scientists have been willing to accept this analysis, but many have not. Frank Drake freely acknowledged that his childhood faith in fundamentalist Christianity had inspired him at the outset to join the search and that many of his coworkers “were either exposed or bombarded with fundamentalist religion.” Although he abandoned the faith in early adulthood, its influence can perhaps be felt in his belief in alien immortality and their desire to teach us how to live forever. Sagan admitted no such inspiration, but his biographer, Keay Davidson, labeled his conviction about advanced benevolent creatures a “quasi-religious belief in alien super-beings… secular versions of the gods and angels he had long since abandoned.” When an earlier interviewer proclaimed, “What you postulate is Angels. Faith, the same old faith,” Sagan disagreed. “Not faith. Calculation. Extrapolation.” His own son and science writer Dorion agreed with the interviewer, calling the scientific quest for alien intelligence a substitute for religion in secular times (Basalla 2006, 13, 198).

Effect of Discovery on Earth’s Religions: Scientists’ Views

Numerous scientists have ventured their opinions about the effect that discovering alien intelligence would have on Earth-based religions, on concepts of God, and on human spirituality in general. In 1951 British inventor and science-fiction author Arthur C. Clarke wrote that some people think that “contact with intelligent but nonhuman races, may destroy the foundations of their religious faith” (Dick 2000, 198), and Davies put it even more strongly in 1983, declaring that discovery “would have a profound impact on religion, shattering completely the traditional perspective of God’s special relationship with man” (Davies 1983, 71). Tarter offers a more detailed analysis of what this effect might be. A contacting civilization would be millions of years old and very stable, she assumes, and the effect of their message on us depends on whether God exists and what kind of message they send. If God exists, then they must have developed a universal religion compatible with science; if they shared secrets of the universe and God, and we could verify it, we might become converted to their belief system. If God doesn’t exist, presuming they could convince us of that, it would undermine our religions. A brief “Hello, we’re here” message, on the other hand, might induce a slow change on Earth religions, as they adapt to the reality and perhaps develop a more universal common belief system here (Tarter 2000).

A discovery that alien intelligent beings might be more advanced spiritually as well as intellectually presents a special challenge to some Earth religions. Davies claims, “The difficulties are particularly acute for Christianity, which postulates that Jesus Christ was God incarnate whose mission was to provide salvation for man on Earth” (1983, 71). If intelligent and spiritually aware aliens exist, then a Christian must face the question of whether Christ died to save only humans on Earth or to save all beings everywhere. And if he died for all, was this accomplished by his one sacrifice on Earth, or does it need to be repeated on an endless number of worlds? Astronomer Milne addressed this question in the mid-twentieth century, reasoning that the Christian would, he imagined, find multiple Incarnations and crucifixions an intolerable thought and reason enough to regard Earth life as unique. His own resolution had an unusual and distinctly modern twist: he speculated that between the stars and even galaxies a vast radio communication network might develop and carry the message of Christ’s salvation to all beings everywhere, thus making multiple atonements unnecessary (Milne 1952, 152-54). Many regard the idea of multiple Incarnations and crucifixions absurd or even comic, while others see it as close to heretical in making automatic and commonplace a special and holy one-time event. Nonetheless, the question is considered seriously by a number of theologians, as described in the next section, and, surprisingly, most display far more flexibility of thought than scientists predict, fulfilling Clarke’s pronouncement that a robust faith has nothing to fear from “collision with the truth” (Dick 2000, 198).

Davies considers that of the other major world religions, Judaism and Islam have fewer but still not negligible difficulties with the existence of extraterrestrials, while Buddhism and Hinduism find the idea the least problematic. He quotes a verse from the Koran that seems to accept the idea: “And among his Signs is the creation of the heavens and the earth, and the living creatures that He has scattered through them” (Davies 2003). Since both Islam and Judaism emphasize the special status of human beings and even particular groups who are the faithful, there is a question whether they could easily accommodate extraterrestrials theologically. For Hinduism and Buddhism, however, the vast conceptions of the universe and greater universality of their religious concepts make accommodation to life beyond Earth seem much more natural (Davies 2003). A similar assessment is made by Dick (2000, 202).

Some reflect on how discovery would affect humanity’s self-image and search for self-understanding. Davies sees the search as a test for the world-view that posits progress and the cosmic preeminence of mind. To find another example of intelligence would confirm our self-worth and “restore to human beings something of the dignity of which science has robbed them … [and] give us cause to believe that we, in our humble way, are part of a larger, majestic process of cosmic self-knowledge” (Davies 1995, 129). For Primack and Abrams, this might happen whether we find aliens or not. If we do find them, perhaps their wisdom will “encompass” ours, much as the theory of general relativity encompassed but did not entirely overthrow Newtonian gravitational theory. Living long enough to experience an encounter, however, we may develop such wisdom ourselves. Even if we never find alien intelligence, or if we are truly alone, to identify those qualities aliens should have to make us not feel alone is a way of studying ourselves. Those qualities are “the essence of humanity … [and] what a long-lived civilization on Earth should aim to cultivate in ourselves” (Primack and Abrams 2006, 234-35).

Historian Dick believes that the widespread acceptance of cosmic evolution and abundant life and intelligence is ushering in a new era of cosmic consciousness in which “cosmotheology” must transform older theologies. Its general principles are the noncentrality of humanity in the universe—either physically or biologically—the low-ranking of human intelligence in relation to others, the need for new conceptions of God “grounded in cosmic evolution,” and the need for a moral dimension of reverence for all life. This perspective will become ever more natural as humanity moves out into the cosmos and reorients itself to a “biological universe.” Actual contact would, of course, accelerate the transformation. He speculates that “in learning of alien religions, of alien ways of relating to superior beings, the scope of terrestrial religion will be greatly expanded in ways that we cannot foresee” (2000, 202). What might require the greatest transformation is our present conception of God. In place of the transcendent creator God of traditional monotheism, a new “natural” God is envisioned—a superior intelligence with many of the same attributes as the Judeo-Christian and Islamic God but a God abiding in nature and not separate from it. Such a “natural God of cosmic evolution and the biological universe,” he claims, holds the promise of harmonizing religion and science and becoming the “God of the next millennium” (Dick 2000, 202-4, 208).

Christian and Jewish Theologians Respond

Christian theologians who address the issue of life beyond Earth generally reject scientists’ assessment that Christianity would be threatened by the discovery of intelligent alien beings. In view of how fully the subject has permeated public consciousness, Christian scholars have considered it too little, according to Lutheran theologian Ted Peters. When they do, however, most openly accept the idea of life beyond Earth and “have routinely found ways to address the issue of Jesus Christ as God incarnate and to conceive of God’s creative power and saving power exerted in other worlds” (Peters 2003, 126, 131). This conclusion applies across the board to Christian scholars, except for those of fundamentalist persuasion.

In the post-World War II era a number of Christian theologians and educators spoke positively about the possibility of life on other planets. German Catholic theologian Hans Kung wrote that “we must allow for … quite different living beings …on other stars of the immense universe,” and the eminent Catholic scholar Rahner considers “the many histories of freedom which do not only take place on earth.” A prominent educator proclaimed that Catholics should know that their beliefs are “entirely compatible with the most startling possibilities concerning life on other planets.” Evangelical minister Billy Graham agreed, announcing his belief that “there are intelligent beings like us far away in space who worship God … [and] are God’s creation.” Certain Protestant theologians chime in enthusiastically on the subject. Krister Stendahl enthusiastically welcomes the idea of communication with extraterrestrials for the way it enlarges God’s universe, and A. Durwood Foster points out that beliefs that accept God’s mystery should find such ideas far from surprising (Peters 2003, 126-27).

In contrast, many conservative and evangelical clergy rejected such beliefs, influenced by fundamentalist literature in the 1970s warning followers against belief in extraterrestrials. According to Peters’ research, three arguments underlie their position. Aliens are not mentioned in the Bible, belief in them assumes affirmation of evolution, which they reject, and the whole business is the work of Satan, tempting the faithful to believe in a source of salvation other than Christ (Peters 2003, 129-31).

A number of theologians also address the thornier issue of the meaning of Christ’s incarnation in the light of other possible civilizations in the universe. Interestingly, views on this subject do not fall along denominational lines. Renowned Protestant theologian Paul Tillich believes that “man cannot claim to occupy the only possible place for incarnation.” In his theology, divinity’s redemptive process is merged with creation and is already active in whatever civilization we might encounter, dispelling the need for us to spread the word to them. From a process perspective theologian Lewis Ford also believes in multiple incarnations of divinity. Because God is present as a persuasive force in every event within the whole evolutionary unfolding, his redeeming action is part of creation and applies to all intelligent beings, wherever and whenever they may exist and be open to it (Peters 2003, 127-29).

Two Roman Catholic and one Anglican theologian also support, or at least do not exclude, multiple incarnations. Rahner agrees that multiple incarnations are conceivable, although knowledge of them is unattainable, limited as we are to revelation pertinent to our own salvation (Peters 2003, 127-29). In Many Worlds, One God, Catholic priest Kenneth Delano expounds on God’s caring love for all intelligent beings in the cosmos and affirms incarnation on other worlds for “any one or all three Divine Persons of the Holy Trinity.” This is a much greater likelihood than a onetime redemption of a “cosmic Adam,” although the latter could provide opportunity for human missionary activity to spread the word. Along these lines, Anglican theologian E. L. Mascall rejects astronomer Milne’s suggestion of spreading the Gospel via radio communication as being insufficient to bring about the special act of union that redemption involves. There is no reason to assume it could not have happened where those needing salvation lived. Mascall delights in “theological flexibility,” declaring “how wide is the liberty that Christian orthodoxy leaves to intellectual speculation” (Dick 1998, 248-50). Such wide-open speculation can lead in many directions, however, and one Catholic philosopher, McMullin, warns against simplistic arguments that fail to recognize the divergence of theological interpretations of the meaning of the Incarnation itself. For him, the cautious answer is “maybe” there could be multiple Incarnations. (2000, 171-72)

The opposite position is also held by both Roman Catholic and liberal Protestant theologians. Jesuit journalist L. C. McHugh and scholar Edgar Bruns both affirm that Christ’s one Incarnation on Earth has universal applicability. For Bruns, “[Christ] is the foundation stone and apex of the universe and not merely the Savior of Adam’s progeny,” a belief echoed by Protestant scholar Wolfhart Pannenberg, who sees Christ as the nexus of being aiming to bring the entire cosmos to a consummate fulfillment (Peters 2003, 127-29).

Regarding the views of Jewish theologians on the subject, one Jewish scholar, Rabbi Hayim Perelmuter, gave a definite answer: “Contemporary Jewish theology would have no difficulty whatsoever in accepting new knowledge regarding the existence of extraterrestrial life.” Such knowledge would but widen the horizons of their conception of what God had brought into being (Peters 2003, 129).