Creationists point to the eye as evidence of design. This is a sorry strategy, because the human eye is not very well put together. But it isn’t the poorness of the design that gets me, though, it’s the inability to explain the poorness that I find most intriguing. This, I find, is absurdly common in religious belief. When confronted with the question of why the eye sees things upside down, for instance, the creationist must shrug his shoulders and proclaim that this is a mystery we are not meant to understand. What this really means, or ought to mean to any plain thinker, is that the badly designed features of the human eye are not explainable from creationism. The end. The “theory” that the human eye was designed and brought into being by a superintelligent creator does not predict eyes with blind spots. One does not start with the proposition that a grand watch-maker built this watch, and then expect to find a watch built completely backward, with hackneyed and awkward solutions to straightforward engineering problems.
It is a generalized failing—not only with religion, although that is the primary culprit. I was having an online discussion with someone about the creation stories in Genesis, and that person’s explication was that it was a metaphor for emergence from an unconscious animal state to a conscious human state. Perfectly good, except that as soon as I began asking detailed questions it was apparent that explaining most of the elements in the tale was impossible. Why are the elements clay and air mentioned specifically in the creation of man? Why a serpent? Why a tree? Why “fruit” on a tree? Why did God go away for awhile? None of these are answerable. So, like the creationist, the proponent shrugs his shoulders and says “I don’t know, it just is that way.”
Maybe it’s just me that’s bothered by that position. While I am alright with admitting ignorance (okay, I barely tolerate admitting that), I am not copacetic with saying a thing cannot be known. I want the final analysis either to explain everything adequately or to temporarily suspend judgment pending new data (with a sensible idea about what this data ought to be, and perhaps with a clue on where to start looking for it). “It’s a mystery” is to me an alien philosophy.
Worse is the cheerleader of a mystery-laden theory who engages in feats of mental gymnastics to try and explain away the fact that the theory does not explain things. It does not matter, they say, that the eye has a blind spot and sees upside down, because those issues are solved in software. The visual processing in our brains corrects the inverted, lossy input, which renders the hardware faults inconsequential. Why, we could even say these flaws are merely neutral, neither good nor bad, and definitely not worth talking about.
That kind of tactic doesn’t help. It doesn’t solve anything. It’s like another of the creationists’ favorites: the universe must have had a First Cause. (Nevermind that it did not need a first cause. They can’t be bothered to learn science before pecking away at it.) This First Cause, the argument goes, this great Uncaused Cause, is God. Why is that the case? Why does God get a Get Out of Causation Free card? Why does the universe need to be caused? Why not say the universe itself is uncaused? What I am getting at is the attempt to make the question go away only pushes the question back one step. You say the eye’s flaws aren’t flaws because the brain makes up for them. Well then why does the brain do that? There is no answer to this question without admitting there was a functional problem that the brain was trying to route around.