The universe has two dozen “physical constants” like the force of gravity that are just right to allow for the existence of atoms and stars and life. Change any of them — most by even the teensiest amount — and we are not here.
Some point to this as proof of God. But physicists mostly have a different take, with many calling this life-friendly physics the Anthropic Principle. The phrase first appeared nearly 50 years ago during a symposium honoring the 500th birthday of Copernicus. Theoretical physicist Brandon Carter disputed the Copernican Principle that humans do not occupy a privileged position in the Universe. Carter startled the audience by saying: “Our situation is inevitably privileged to some extent” and then announced two forms of the Anthropic Principle still debated today. The weak version essentially argues that physical constants such as the mass of the proton had to be what they are for life to exist, otherwise no one would be around to wonder about it. If we’re here, all these things have to be the way they are, and there’s no oddity or coincidence that needs to be explained.
Well, okay, but is this science? Or philosophy? Or is it circular reasoning?
The Strong version of the Anthropic Principle goes much further. Resembling the writings of Aristotle, it argues that life or observers are either coexistent with the cosmos, or that the universe’s goal and plan was to produce us, so that the various physical properties pivotal to our existence had to arise.
Since this version suggests that intelligence and strategies lurk behind the cosmos, it is brushed off by even most religious scientists as untestable and thus a morsel of philosophy or theology, and not science at all.
So we’re back to Square One, with a cosmos whose physics is amazingly fine-tuned for the existence of observers. And a science community wondering if the Anthropic Principle really explains this. What do you think?
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