Does the perfection of the human eye prove that it was created?

The short answer

Everything in the biological world is imperfect, the human eye included, so the question is moot.

The longer answer

Although the human eye works to a degree that is consistent both with evolution and with a smart group of MIT undergraduates, it isn’t perfect. A common example of the imperfection of the human eye—though not by any means the most obvious—is the generation of blind spots by the inversion of the human retina. As is the case with all vertebrate retinas, the human retina is inverted so that its photoreceptors (the cells that detect light) face away from the iris and their wiring (so to speak) points into the center of the eye. While the inversion may have some advantages, it creates the need for a hole in the retina through which the wiring can connect with the optic nerve. These holes, in turn, create a blind spot in the visual field of each eye. These blind spots normally are not a horrendous problem for us—most of us probably go through our entire lives not realizing they are there—but one would hardly say of them that they represent perfection.

There are, of course, far more obvious ways in which the human eye is imperfect: for instance, our eyes suffer from all of the standard afflictions of the human body, including vulnerability to trauma, to disease, to aging, and to wear and tear. These are normal things to expect from the products of unguided natural processes, but not what one would consider the perfect engineering of a creator god. Remember that when people talk about a creator god, they are talking about a being whose power supposedly is unlimited, unconstrained even by the laws of nature themselves; had such a being wished to go so far as to make our eyes out of some invulnerable quintessence (with no blind spots), there would have been nothing to stop him. One might hold—though the Bible never says anything of the sort—that the eye originally was perfect, and that God later introduced deficiences into it when he banished Adam and Eve; however, this still would undermine the claim under analysis, since the question is about the eyes that we have now.

Imperfect engineering is apparent in far more than the human eye, and extends beyond the normal vulnerabilities of flesh. Useless or inefficient structures that appear to be relics of distant ancestors abound in the natural world; for instance, there are the hollow bones of flightless birds, the clumsy thumb of the giant panda, and the vestigial pelvis of pythons and whales (Futuyma 1983:198-200). Evolution is ingenious, but nothing in the natural world is perfect.

I discuss elsewhere the claim that the eye could not have evolved gradually, and the claim that Darwin himself thought that the eye could not have evolved.

References

Futuyma DJ. 1983. Science on Trial: The Case for Evolution. New York: Pantheon.