David Barash wrote an op-ed on imperfections in human design that I'll get to in a moment, but right now I'm most interested in this set of letters to the editor complaining about the piece. There are several false claims about the basis of intelligent design in evidence:

The modern ID movement simply points out ample evidence of design (vs. chance or randomness), not perfection (vs. imperfection).

…"intelligent design" - which specifically refers to the empirical evidence that points to the very high probability that a "mind" was at work sometime in the creation of life…The irreducible complexity of life, as is evidenced by the numerous interdependent molecules, cells and organ systems, each of which cannot function without the other (for this is the basis of medical science), points to the intelligent design of life and away from what is promoted by Barash, i.e., all life having come about exclusively by the random forces of nature.

None of this is true. There is no evidence for Design and no body of empirical support for the claims of the Discovery Institute; "irreducible complexity" had its brief moment of glory in the 1990s, was quickly found to be trivial, uninteresting, and wrong and was discarded from consideration on first reading of Behe's book by every competent scientist. Waving one's hands at big piles of complexity is not an argument against evolution, which is very, very good at accumulating messy contingencies. Nor is it an argument against randomness; there is a corner of my garage where we tossed the unsorted debris from our last house move that is extraordinarily intimidating in its complexity, which is why we haven't managed to make a dent in it yet in the last two years.

And please…nobody should be bringing up this bogus claim of "all life having come about exclusively by the random forces of nature". Evolution is not random, OK?

Barash brings up several suboptimal features of the human body—backaches, childbirth, urogenital plumbing, etc.—that are reasonably explained by our evolutionary history. How do these letter-writers explain it using Intelligent Design "theory"? There is the usual excuse of the Fall of Man—we're being punished for our Edenic naughtiness.

We know from biblical passages like Romans 8 that the entire creation is "groaning" for the time in the future when things will be set right (perfect) once again. The Bible never makes the claim that our present bodies would be free from pain or deterioration. But the biblical text does speak of "new bodies" that God will provide, which will be perfect.

There is the "testing" argument: God does it on purpose, giving us arthritis and cancer and crippling injuries to make us better people. I call this one the Sadistic Daddy theory of design.

Our bodies were designed to age and eventually to wear out. It is part of a loving creator's plan to place challenges and obstacles in our path and then to help us overcome them so that we may become stronger, wiser and better. It is also part of the plan that when we have completed our task here in this life we should then move on to the next step in our progression.

I thought this one was theologically interesting—the author wanders a bit off the religious reservation to suggest that God was a bit of a putterer. It's still a poor fit with evolution, though, because evolutionists do not argue that prior forms were failures.

Nor do we believe that the human body is perfect. It has been cobbled together. Like Thomas Edison or any great inventor, there were many trials and errors before there was success.

Don't assume that the last writer was a member of the nearly invisible rational-materialist wing of the ID movement who at least pay lip service to the idea that intelligent aliens did it, though: he starts his letter off this way:

It is evident from reading David Barash's column that he either does not understand what intelligent design theory is, or he is simply dogmatically opposed to it since it relies on the existence of God.

That's another interesting theme of these letters: they all babble out little dollops of Discovery Institute approvable pseudo-secularism, mentioning science or reason or evidence and trying to slap together some sort of rationale that doesn't require simple miracles, but at the same time all also fall back on God. These are religious people who are ultimately basing their adoption of Intelligent Design "theory" on the fact that it appears to provide a rational framework for religious and necessarily irrational beliefs. No one says it plainer than this one:

Intelligent design appeals to intelligent people who have a rational belief in God.

Intelligent people, maybe—but not quite intelligent enough to either a) discard the superstitions of their forefathers, or b) recognize that religious belief is not built upon empirical evidence, and cannot be verified by the tools that are extremely good at probing the material world.

As is common, these writers completely misunderstand the argument from imperfections that Barash presents; they treat it as an argument for atheism, rather than evolution. It isn't. It can be used as an extremely hypothetical argument about the nature of god, I suppose, which is how these writers treat it and as Barash briefly mentions (admitting that these observations could be accounted for by a god of "incompetence or sheer malevolence"), but as an argument for evolution, this is irrelevant. These imperfections are seen as relics of our past history, and indicate that we did have a complex history—we were not born as a species with no heritage from our forebears.

For example, I have a large scar on the lower right quadrant of my abdomen. An objective doctor could look at that and from its position and the degree of healing determine that I had an appendectomy many years ago. He could do tests to evaluate that inference about my history—open me up and see that I don't have an appendix, for instance—and all he would be doing is making a conclusion based on the actual physical evidence. Speculating that I had been born with the scar, that it was punishment for my father's sins or that it was done to test my faith, are not relevant to the material facts.

And that is the argument that Barash is making. Our backaches are a consequence of our posture and our anatomy, which show clear ties to the organization of our quadrupedal relatives. There's no judgment of punishment here—just signs of physical relationships that suggest historical events.