In this article I discuss some of the implications of Intelligent Design, implications that may not have occurred to its believers. Putting aside, for now, the validity or otherwise of Intelligent Design, I argue that–using the believers’ own arguments–it is possible to show that God is not the Creator. I do this by showing that the human body, rather than being the creation of a perfect god, is in fact a sign of engineering incompetence.
As the main part of my argument, I do this by discussing the design of the human eye. I could use other parts of the human body to demonstrate my point, since there are many of what can only be called badly engineered systems and organs within it, but it seems most appropriate to use the human eye as my example given that believers in Intelligent Design often claim that the human eye is the best argument against evolution. They picked it first; I’m just going along with their choice.
Believers in Intelligent Design claim that the human eye is too complicated to have evolved from anything simpler. They say that if it had evolved there would, for example, be some creatures that had only half an eye, which, so they say, would be useless because it wouldn’t work. They argue that only a complete eye, such as the human eye, can be of any use.
Evolutionists have answered these claims by arguing that the human eye could have evolved. Beginning with a light sensitive patch of skin, plus a few million years of evolution, a working human eye–or something very similar–could result. And even though the intermediate results might not have been very good, they would have been better than nothing.
In fact, even half an eye is useful; it is better than no eye at all. Having half an eye is a better survival strategy than not being able to sense light at all. Being able to detect the difference between light and shadow would increase a creature’s awareness of its surroundings and of approaching dangers. Since it would aid survival, that is all that evolution needs to eventually produce a human eye.
Believers in Intelligent Design assume that features such as the human eye are perfect for the job they do. This must be so, they say, because they were created that way. However, the human eye is not perfect. It does a good-enough job to be extremely useful, but it is very far from being perfect.
Professor Greg Downey of Macquarie University, in a lecture on the evolution of the human eye, made the comment that if a first year engineering student handed up a plan for the human eye as a design for an organ of seeing s/he would be immediately failed and told to redo it properly. If a first year engineering student could do better, what does that say about the creator? (This question will be discussed in more detail below.)
One of the worst design faults in the human eye is the way in which information from the light sensitive cells of the retina are passed to the brain. The output of the light sensitive cells is actually taken from the front, in the direction from which the light is coming and entering the cell. This means that the connection from the light sensitive cell to the nerve cell partly blocks off the cells in the retina, reducing its efficiency and sensitivity. Worse, those nerves then pass across the front of the retina, again blocking off some of its sensitivity. All the nerve cells exit the eyeball through one fairly large opening. This means that part of the retina has no light sensitive cells, thus producing a blind spot. We don’t usually notice this blind spot because the brain fills in the gap by extrapolating from the data coming from other nerves. But it is there, and its existence can easily be shown by a simple experiment that can be found in any book that discusses the eye and vision.
I have no reticence in saying that any competent designer of the human eye would have avoided these problems by taking the nerves out of the back of the light sensitive cells in the retina. No exit hole for the nerves would then be necessary and there would be no blind spot in a person’s vision, and no loss of sensitivity due to the nerves blocking off some of the retina. It seems safe to say that the human eye was not designed by a creator with the engineering competence of a first year engineering student In fact I would go so far as to say that the designer was completely incompetent, yet this is the incompetent design that believers in Intelligent Design want to lay in the hands of their God, the alleged Creator of humankind.
God is said to be perfect, omniscient and omnipotent, however, so s/he could not be incompetent nor make a mistake. Therefore, if god were the creator, then the human eye would necessarily be perfect. It would not have any of the faults described above. It follows, then, that God did not create the human eye, nor, assumedly, the rest of the human body, which also has faults that would indicate an incompetent engineer.
If God did not create humans, who did? Was there a creator other than God?
I think that it is unnecessary to follow that thought any further. It is enough to say that, using the arguments put forth by believers in Intelligent Design, the same kinds of arguments can be used to prove that they are wrong.
Evolution is the answer to the origin of the very imperfect, but very useful, human eye. Believers in Intelligent design are simply wrong.