Keller’s third clue to the existence of God is the regularity of nature. Meaning that observations of the past are useful for predicting the future. Keller says that this feature of the universe is taken for granted and overlooked, but that science depends on it. He admits that this is not rock solid proof, since one can always say, “We don’t know why nature is regular,” but contends that it is a clue to the existence of god nonetheless.
Unfortunately, for those who want to believe in a god, this “clue” is just an extension of the last clue, that the cosmos is nice for life. As a result my arguments against clue 2 also work here.
It is true that science relies on the basic laws of the universe remaining the same to function (or at least very close to the same) but science is not the only thing that relies on this. Suppose the laws of the universe were free to change within bounds that would allow life to develop, at random. So, things could change quite dramatically, but slowly enough for life to adapt to it, and nothing so drastic as to make matter incohere or planets dissolve. Life in such a universe would be challenging, but possible. However, intelligent life would never evolve. In such a universe knowledge of the past would not be useful in predicting the future, so evolution would not favor intelligence beyond reacting to immediate threats. Memory would not need to last, tool making would be impossible, since the way to make and use a tool would change frequently, etc. Basically, life like us would not exist to question why the laws of nature are so changeable. In this way it is exactly like the cosmological constant argument, either life like us can exist, or it can’t. In the case that it can’t, we can’t know it, so it is impossible to determine the odds of these things.
You can also think of this as just another cosmological constant. A nob that defines how quickly the other constants change, or within what range. In our universe they change very slowly, or within very small margins, or not at all. This is now just another aspect of the “fine tuning” of the previous “clue” that I argued against.
My final problem with this “clue” is that the regularity of nature doesn’t suggest there is a supreme intelligence at all. In the bible God is always messing with the laws of the universe to perform miracles. Modern Christians, and other religious people, argue the miracles still happen and pray for specific ones. The regularity of nature actually argues against a god, or at least against a god that interferes in our lives.
This “clue” really just seems like desperate padding.