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The Complexity of the Universe is Evidence Against the Existence of a Creator Deity: The Argument from Unnecessary Complexity

The purpose of the present essay is to argue that the complexity of the universe is evidence against its having been created by a deity, and particularly, against its having been created with special consideration of human beings.

Let us consider bats. (This example is used solely because it started the train of thought that resulted in this essay.) A typical bat is a winged, insectivorous mammal. It locates prey by emitting high-pitched sounds that are reflected from a potential meal to the bat’s ears (echolocation). Some species of moths have evolved a defense against bats; they are capable of perceiving the bat’s sounds and their response is to stop flying and drop toward the ground. The effect is to remove them from the bat’s field of echolocation.

The question arises, if God made bats and moths, why create this complex situation? If God intended bats to eat moths, why give some moths a defense against bats? One cannot argue that “he” also intended moths not to be eaten by bats. The existence of a moth defense is an unnecessary complication in the biosphere. It is, however, what one expects if predator and prey attained their present states by evolution. Moths that “heard” bat sounds and did something to evade them survived to leave offspring more reliably than moths that did not do these things.

There are about 1,000 species of bats. God may have wished to make a nocturnal, winged, insectivorous mammal–but why make so very many kinds? Surely a much smaller number would have sufficed for a diverse and functional biosphere. The existence of numerous species of bats would, however, be predicted by evolution. There are few species of nocturnal insectivorous birds; bats have this large ecological niche pretty much to themselves, and evolved into many species to take advantage of all the subniches within the night skies over the temperate and tropical parts of the earth. Similar subniches in different parts of the world were occupied by different species of bats derived from ancestral species present in each part.

A bat is built to be an insectivore. There are, however, bats that eat nectar, flowers, fruit, blood, fish, frogs, lizards, birds, rodents–and other bats. Some of these noninsectivores use echolocation to detect prey; some do not. If God designed an insectivore, why would “he” simultaneously make animals of the same kind, with the same basic anatomy and physiology, that consume a variety of foods radically different from insects? This is an unnecessary complexity. It is, again, what evolution would predict. Many kinds of food are available to nocturnal fliers, and where there was no established or evolving competition that largely excluded bats from diverse dietary relations, they evolved to take advantage of these opportunities.

When asked to explain this profligate multiplication of species of bats and types of vespertilian behavior, creationists will reply that it demonstrates the boundless creative capacity of God. But if there had been only a few species of bats, creationists would have said that God created just enough kinds to serve whatever divine purpose they attribute to bats. If there had been a single species, they would have said that God created a perfect flying mammal and had no need to create others. One perceives that creationism does not provide an explanation of anything. If any matter were different than it actually is, one could always suppose a plausible reason for a creating deity to have arranged things in this different manner. To state that anything is as it is “because” a deity willed it that way is an attribution, not an explanation. A hypothesis that can be alleged as the reason for anything whatsoever has no explanatory power. It is merely a cloak to conceal ignorance of actual causes. (One should note that not until the 19th century, and then only among educated people in Western culture, did humankind possess more correct ideas about the universe than false ones.)

Evolution, however, actually explains the diversity of bats and their behaviors–and why there are not only a few species. It does so using principles that are exemplified throughout the biosphere. And unlike the putative agency of immaterial beings, the theory of evolution can be subjected to evidential reasoning.

Examples of unnecessary complexity from biology could be greatly multiplied. To mention just one more: immense numbers of microorganisms, belonging to very many species, live in countless environments. They have no demonstrable effect on humankind. What kind of frenziedly profligate designer would have populated the soil, hot springs, and Arctic waters (to mention just a few environments) with this immense variety and number of obscure organisms?

At this point the creationist may say, “God made these complexities to impress us with his diversity and ingenuity.” But whom did “he” intend to impress? Knowledge of the kinds of facts described above has been acquired only recently and still is confined to a small number of scientists and other educated persons. The vast majority of human beings who have ever lived could not have been impressed by the diversity of bats or bacteria.

As already mentioned, all these situations are evidence of evolution. The creationist likes some facts of biology–those that he can accommodate in his closed system of thought–and accepts them. He dislikes other facts of biology that are contrary to his system of thought–such as all the evidence of life on earth and the human species being vastly older than his system teaches. He denies the factuality of these and tries to explain the observations in an idiosyncratic manner. This is cherry picking, and it is invalid in any argumentation. From bats let us proceed to the cosmos. The Ptolemaic universe–which the Christian Church defended against scientifically superior concepts–was suited to creationism. Earth was exactly in its center; the planets moved around the earth in perfect circles, as did the stars, which were all equidistant from earth.[1] Occasional aberrations such as comets and meteors were said to be intended as signs and wonders. The whole was not very large, and it was contained by an outer sphere as if in a box. The only persistently irregular feature was the occasional apparently retrograde movements of the planets, which required the insertion of epicycles into their orbits. (This was, however, an element of unnecessary complexity for which a theistic explanation is not evident.) A common argument for the existence of God is, “Look at the night sky. What explanation can there possibly be for what you see other than that God made it all?”

The actual universe, especially if it is conceived as having been created so as to serve human needs and to inspire humankind with awe and thereby manifest the glory of The Trinity, is in most of its characters unnecessarily complex. It is hugely in excess of what would be needed for these supposed purposes with respect both to its magnitude and the numerousness of its components. It is extravagantly wasteful of both matter and energy. The reflecting planetary spheres of Ptolemy and the lamp-like stars suggested intelligent design. In contrast, immense quantities of invisible dark matter,[2] and of gases; stars emitting radiation other than visible light, and with cyclical variations in their emissions; dead stars and collapsed stars (black holes) that emit no light–all these have been undetectable and unknown until very recently in human history, and are superfluous for manifesting glory and inspiring awe. The perception of God in the night sky is not an observation, but a construction the viewer construes what she sees to make it accord with hypotheses about immaterial beings that in themselves convey no information whatsoever about the characters of the universe.

The supposed orderliness of the universe is a misconception based on a simplistic theory of celestial motions and made possible only by ignorance of most of the components of the universe and their behavior. The cosmos has no detectable boundary, and the galaxies are moving away from one another into what as far as we know is empty space. All of this complexity serves no human purpose, and none of it indicates intelligent design.

There is no difficulty, however, accounting for this “superfluous” complexity if one accepts the evidence for a naturalistic origin and evolution of the universe. Much of it can be explained from the initial conditions and the regularities (“laws”) that human beings use to describe the behavior of nature (Harland; Stenger).

As in biology so in cosmogony and astronomy. Biblical literalists accept facts that they like. Those they dislike–such as those that demonstrate that the universe is more than 2.5 million times older than the Bible states–they deny, and try to explain the observations in an idiosyncratic manner–by magic, if necessary:

If the universe is no more than ten thousand years old … as I believe Scripture plainly teaches, how can we see light that theoretically should have taken millions [or billions] of years to reach us? … It seems clear that when God created the stars, because He created them to illuminate the earth [sic] and be signs of our seasons, He also supernaturally enabled the light to traverse those vast expanses of space immediately. (MacArthur 118)

At the other extreme of size, Christians, after opposing atomic theory for centuries, have been forced by science to acknowledge that atoms exist. A designing God could have made simple atoms of the kind envisioned by physicists over a century ago. The actual nature of the atom–with a multitude of component parts with complex properties and interactions–is not economical or straightforward. It does not suggest design. Projecting their beliefs onto the universe, creationists like to allege that the evidence of design is plain to the understanding. There is, however, no ready understanding of subatomic events such as this:

By emitting an X-boson, a ‘u’ quark can transform into the corresponding antiquark. If the X-boson were to be absorbed by a nearby ‘d’ quark, this would turn into an anti-electron. If the X-boson did not find another quark to interact with, it could decay into a ‘d’ antiquark and an anti-electron … X-bosons could both create quarks and leptons and turn quarks into leptons. (Harland 233-4)

And the universe on the smallest scale postulated by superstring theory (Greene) makes quarks, leptons and bosons seem simple.

To conclude: creationists often argue that the complexity of organisms cannot be explained by science, and demands the hypothesis of a divine creator. The present essay reverses this argument: biological complexity cannot rationally be attributed to intelligent design, but it is explained by the fact of biological evolution. Similarly, the complexity of the cosmos is not consonant with a hypothesis of orderly, reasoned creation, and evolutionary scientific theories alone make this complexity comprehensible. Attempts to perceive divine interest in humankind in supposed orderliness of the universe founder on the facts of complexity, which manifest the absence of intention.


[1] Newton’s laws of motion often are said to have resulted in a concept of a “clockwork” universe, and that word often is used pejoratively with the implication that the concept is simple-minded. In fact, it was the Ptolemaic model in which celestial motions resembled those of the moon dial on a hall clock. From the time of Kepler–two generations before Newton–celestial movements came to be perceived less and less like clockwork.

[2] Stenger (2007) points out that with respect to its character, “most of the matter and energy of the universe exhibits little structure and shows no sign of design” (162).

Works cited

Greene, Brian. 2000. The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory. New York: Vintage Books.

Harland, David M. 2003. The Big Bang: A View from the 21st Century. London: Springer-Praxis.

MacArthur, John. 2001. The Battle for the Beginning: The Bible on Creation and the Fall of Adam. Nashville, TN: W Publishing.

Stenger, Victor J. 2007. God: The Failed Hypothesis–How Science Shows That God Does Not Exist. Amherst, NY: Prometheus Books.