Objections to the Argument from Design
The argument from design is the argument that the fitness of the universe for life is evidence that it was created with life in mind. This is one of the most popular arguments for God’s existence, and is still hotly debated today.
Darwin’s Theory of Evolution
Atheists often reject the argument from design as having been refuted by Darwin. Perhaps once, when we understood the world little, they sometimes suggest, it was plausible to think that the appearance of design in nature was a good reason to believe in God, but now we know better.
We can now explain how complex organisms came about, and why the universe so closely matches the needs of its inhabitants, in terms of Darwin’s theory of evolution. Complex organisms evolved over time, and the universe was not designed to fit life, but rather life evolved to fit the universe.
With the advent of the theory of evolution, it is claimed, we no longer need to invoke God to explain the order of the natural world.
Responses to Darwinists
This objection is fine as far as it goes. Some early design arguments did take the order and complexity of biological systems such as the eye and invoke God as an explanation of them. The theory of evolution can now explain how simple organisms developed into the complex beings that we see around us, and indeed are ourselves. It may be, then, that these arguments are no longer compelling. (For more on this, see Can Evolution Explain Our Origins?)
The theory of evolution, though, even if it is accepted, can only explain so much. In order for evolutionary processes to get going, a specific set of conditions must hold: there must be a universe with certain natural laws, there must be an environment capable of supporting some primitive form of life, and there must be organisms that are able to reproduce, for example.
Evolution cannot explain how the circumstances necessary for evolution to take hold came about, because until they came about there could be no evolution. Many design arguments, including that described on this site, find design in phenomena that the theory of evolution cannot explain, such as the circumstances of the big bang. Such arguments are immune to the objection that they have been rendered obsolete by Darwinism.
The Weak Anthropic Principle
Another objection to the argument from design rests on what scientists call “the weak anthropic principle”. The weak anthropic principle is the principle that in order for the universe to be observed it must be such as to permit the existence of observers, and that there is therefore no need to explain why we observe the universe to be fit for habitation.
If the universe were unfit for habitation, atheists suggest, then there would be no observers, and so the universe would not be observed to be unfit for habitation. All observations of universes must therefore be observations of universes fit for habitation. There is no need to explain why we observe the universe to be fit for habitation; we could not possibly observe it to be otherwise.
This objection rests on a simple misunderstanding of the argument from design. The argument from design does not take the fact that we observe the universe to be fit for habitation as its starting point, and seek to explain what we observe. Rather, it takes as its starting point the fact that it is possible for us to be here to make observations at all. A story is told to illustrate the fallacy behind this objection to the argument from design:
A man is taken blindfolded before a firing-squad. A hundred trained marksmen aim their rifles at him, and, on the signal, they shoot. The man hears the shots, and for a moment is surprised. Bullets travel faster than the speed of sound, he reasons. With a hundred bullets flying towards his head, he should be killed before he hears anything. He can only have heard the shots because every marksman has missed. Then he sees things a little more clearly. Had the bullets been on target, he would not have heard a thing, because he would have been killed instantly. The only observation that he could possibly make is of the marksmen missing. There is therefore no mystery about the marksmen missing, nothing that needs to be explained.
Of course, there is a mystery about the marksmen missing. It is not surprising that, given that the man observes something, what he observes is that the marksmen have missed; it is surprising, however, that he is alive to observe anything at all. The same is true of the design in the universe. It is not surprising that, given that we observe the universe, we observe it to be fit for habitation; it is surprising, however, that we are here to observe anything at all.
The Many Worlds Hypothesis
A final objection to the argument from design rests on the many worlds hypothesis. The many worlds hypothesis holds that this universe is not unique, that there are many alternate universes that are inaccessible to us. One variant of the many worlds hypothesis holds that these alternate universes correspond to possible state of affairs, that everything that is possible is actual in some world somewhere.
If the many worlds hypothesis were true, then that would present a problem for the argument from design. For the argument from design claims that it is unlikely that there exists a universe fit for habitation by chance. The more universes there are, the more likely it is that one of them will support life. Given an infinite number of universes, instantiating every possible state of affairs, it is certain that life will exist somewhere.
If the many worlds hypothesis is true, then it completely undermines the argument from design. If we are ready to endorse the many worlds hypothesis, then we can reject the argument from design. How plausible, though, is the many worlds hypothesis? Is this too high a price to pay for unbelief? In my opinion, the claim that every possible state of affairs is realised in one of an infinite number of parallel universes is far less plausible than the claim that God exists. I can believe the latter; I cannot believe the former. I therefore cannot reject the argument from design based on this objection. The apparent fine-tuning of the universe for life does seem to me to be powerful evidence that it was purposefully created with life in mind.
The next argument, the moral argument, claims to provide an insight into what God’s purpose is for his creation.