ABSTRACT
The universe is fit for human survival. The anthropic principle is an attempt to account for the fact that the universe seems “finely tuned” for human life by showing that, in some sense, the universe must be habitable by beings like us. Discussion of the anthropic principle is considerably complicated by the fact that several principles commonly called anthropic are, though formulated in roughly the same way, of quite different status. The anthropic principle is motivated by a desire to explain the fact that minor alterations of basic features of the world—conditions in the very early universe, the values of physical constants, the strengths of the fundamental forces, and the masses and charges of subatomic particles, for example—would have rendered the universe unsuitable for human habitation. The status of the anthropic principle as a scientific principle depends largely on its success as an explanatory and predictive principle.
