They need not be little, of course, nor green, nor, for that matter, come in more than one sex: indeed (with apologies to most episodes of Star Trek), they probably wouldn’t recognizably be “men” at all. But extraterrestrial intelligent life would need to be intelligent — meaning, operationally, able to manipulate electromagnetic radiation to carry signals.
“This is necessary,” argues Paul Davies in his new book Are We Alone? Philosophical Implications of the Discovery of Extraterrestrial Life (New York: Basic Books, 1995, 160 pp.), “because radio contact with aliens is possible only if the aliens are intelligent enough to possess the necessary technology” (p. 89). Should that message be received by our radio telescopes, its effect, Davies argues, could only be momentous:
There is little doubt that even the discovery of a single extraterrestrial microbe, if it could be shown to have evolved independently of life on Earth, would drastically alter our world view and change our society as profoundly as the Copernican and Darwinian revolutions. It could truly be described as the greatest scientific discovery of all time. In the more extreme case of the detection of an alien message, the likely effects on mankind would be awesome (p. xii).
The effect would be awesome, Davies continues, because in an important sense it would refute the Darwinian revolution of the 19th century. In Are We Alone?, Davies makes his case for this conclusion. It’s a case with several byways and tangents, and skeptics observe that the religious implications Davies wants to draw are weakly supported by his case, a criticism which illuminates the philosophical vagueness of concepts such as “contingency,” “determinism,” “randomness,” “progress,” or its absence, all of which play key roles in the positions Davies attacks, and in his own speculations.
Despite its tangents, however–or perhaps because of them!–Davies’ book is well worth reading. As the first scientifically-trained winner of the Templeton Prize for advancements in religion (1995), Davies shows an acute and admirable appreciation for the larger philosophical implications of origins theories. Furthermore, he understands the shortcomings of conventional evolutionary explanations. Take, for instance, the origin of life:
The main reason why the origin of life is such a puzzle is because the spontaneous appearance of such elaborate and organized complexity seems so improbable. In the previous chapter I described the Miller-Urey experiment, which succeeded in generating some of the building blocks of life. However, the level of complexity of a real organism is enormously greater than that of mere amino acids. Furthermore, it is not just a matter of degree. Simply achieving a high level of complexity per se will not do. The complexity needed involves certain specific chemical forms and reactions: a random complex network of reactions is unlikely to yield life (p. 27).
This passage, which echoes the notion of specified complexity employed by design theorists (see, e.g., Thaxton et al., The Mystery of Life’s Origin [New York: Philosophical Library, 1984], 131), is followed a few pages later by a careful analysis of the real probability bounds set by cosmology. In brief, in the cosmic gamble for the origin of life one can spin the wheel (or reach into the urn) only a finite number of times, because the pool of opportunities is not inexhaustible:
Even if the universe is spatially infinite, and contains an infinity of galaxies, we can only even see a finite subset of them. Therefore, if life is a random accident of infinitesimal probability, then it is almost certain that there is no other life within our particle horizon at this epoch, even though (assuming the Copernican Principle) there may be infinitely many inhabited planets in the universe as a whole….We can now see why, if the odds against the random formation of life are so great, there is little to be gained by widening the trial space from planet Earth to all Earth-like planets and then appealing to the panspermia hypothesis. Because no object may travel faster than light, no micro-organism may reach Earth from beyond our particle horizon.
Hence the trials that are relevant to life on Earth must be restricted to the 1010 or so galaxies within the observable portion of the universe. These galaxies may contain a total of, say, 1019 Earth-like planets. But faced with odds of 1040,000 to 1 against, multiplying the trial rate by 1019 has a negligible effect on the outcome (pp. 32-33).
These (and other) passages in Are We Alone? make the book appealing to design theorists looking for thinking outside the usual boundaries. But other passages, and in fact the main thrust of the book, will be disappointing.
Davies recognizes that a theory of intelligent causation need not commit one to invoking “miracles,” meaning events which transgress known regularities of nature; i.e., “design” does not ipso facto violate any natural laws:
…We can contrive to produce highly non-random processes (such as unusual card sequences) without violating any laws of physics, so presumably a purposeful Deity could also do this.
Yet he immediately reverts to methodological naturalism:
Nevertheless, it is the job of the scientist to try to explain the world without supernatural purposive manipulation, and a number of scientific responses have been made to the problem of the enormous odds discussed above (p. 29).
The solution Davies favors?
The laws of physics have the remarkable property that they encourage matter and energy to evolve spontaneously from simple intial states towards highly complex states (such as living or conscious systems). This general self-organizing tendency in nature suggests that the emergence of life is a universal phenomenon, rather than a miracle or a highly improbable accident. …Evidently stupid matter has a sort of innate ability to organize itself. There are many, many other examples in nature….we can imagine a very long sequence of such self-organizing steps in which inert matter goes in at the top and mind comes out at the bottom. That is, if we accept that mind is an emergent phenomenon requiring a certain critical level of complexity, we can imagine that level of complexity being achieved, given long enough, and given the inherent self-organizing tendencies that we find in matter and energy (pp. 102-103).
Yet the examples of “emergent phenomena” that Davies offers are either irrelevant–the “wetness” of water, and the arrow of time (his illustration of the latter is molecules of perfume diffusing in a closed room)–or beg the question.
Davies says that life itself is an emergent phenomenon, arising “only when matter reaches a certain level of complexity” (p. 100). True enough, but calling a phenomenon “emergent” or “self-organizing” hardly engages the question of how the necessary level of complexity is reached. Life and consciousness emerge when the conditions are right, as they must be, argues Davies, but he fails entirely to specify those conditions, beyond arguing that somehow they were built into the universe from the start, as a “sort of ?law of increasing organixed complexity'” (p. 105).
Well, as the famous street-wise equation tells us, ill-defined laws of that variety plus 65 cents = a cup of coffee. To say that life, intelligence, and consciousness are inevitable, never mind the details, is not to solve the problem of their emergence, any more than saying that they are the accidental products of a cosmic roulette (a view Davies strongly rejects).
Davies’ words have a high-sounding ring:
I conclude…that consciousness, far from being a trivial accident, is a fundamental feature of the universe, a natural product of the outworking of the laws of nature to which they are connected in a deep and still mysterious way. (p. 128)
It is unclear, however, aside from tantalizing but vague adjectives like “deep” and “mysterious,” how this really differs from Darwinism, either of the classical variety or later fillips. Stephen Gould, for instance, argues that he fully expects intelligent life to exist elsewhere in the universe (see his interview with John Horgan, “Escaping in a Cloud of Ink,” Scientific American August 1995, pp. 37-41). Writing in the New York Times (12 July 1995, p. B4), critic Richard Bernstein scratches his head about significance of Davies’ dissent:
What remains elusive…is why this “cosmic connection” is contrary to Darwinian law. If random variation and natural selection produced consciousness on earth, why would the same random variations not occur elsewhere in a universe with billions of other planets? If it did occur elsewhere, one could believe in extraterrerstrial life without ditching orthodox Darwinian thought, and without recourse to a mystical, semi-religious concept that makes us feel connected to something really big.
Thus, E.T., should he ever turn up with his glowing finger, would apparently both refute and support Darwinism. One must say “apparently,” for the key terms in this dispute–contingency, determinism, and the like–are too ill-defined to rule out empirical possibilities. One wants a gutsier and more precise metaphysics from Davies than he provides.