Return to my Science pages
Go to my home page
© Copyright 2002, Jim Loy
Nature seems to be finely tuned to support "life as we know it." In fact, it seems to be tuned to supporting and producing human life. This observation leads to the two anthropic principles which conflict with each other:
The strong anthropic principle begins with the above observations, and goes further. The universe is tuned to produce us. A small change here or there, a change in the Earth's distance from the sun, or in its orbital eccentricity perhaps, and human life would not be possible. A deduction that can be made from this is that the universe was designed for us, that this is strong evidence of God.
The weak anthropic principle is similar, but reaches a quite different conclusion. Certainly nature is fine tuned to life as we know it, and to human life in particular. But make a small change in nature, and life will be much different. It is hard to predict just how different life would be. And beings on that quite different Earth (or some other planet somewhere) would be marveling at how nature is so finely tuned as to produce life as they know it. The deduction here is that the fine tuning is natural, and is not such a great coincidence. And the strong anthropic principle is an unwarrented leap of logic.
Of course some changes to nature, changes to the laws and forces of physics, may prevent life of any kind (or even stars or planets) from being or forming. And so there is some real fine tuning of nature, on some levels. And we may see that as great luck, or as evidence of God.
By the way, there is an even stronger anthropic principle, a principle that you (some of you) may actually believe, that the universe is fine tuned for you.