When one theory is simpler than its competitor, this fact is relevant to saying what the world is like.

The rabid opposition to group selection has now considerably subsided. In the process, the conceptual structure of evolutionary theory has become clearer, as have the relationships that connect different theoretical approaches.

Group selection and individual selection are just two of the selection processes that have played important roles in evolution. There also is selection within individual organisms (intragenomic conflict), and selection among multi-species communities (an idea that now is getting attention in work on the human microbiome). All four of these levels of selection find a place in multi-level selection theory.

Instead of thinking of the question of race genealogically, and leaving it open whether vernacular races are genealogical units, the interest in biomedicine has been to determine whether vernacular racial categories are medically useful in diagnosis and treatment. There is on-going debate about this.

Deism is logically compatible with evolutionary theory for the simple reason that the theory says nothing about the origin of the universe or of the laws of nature.

If you have evidence that C1 is a cause of E, and no evidence as to whether C2 is also a cause of E, then C1 seems to be a better explanation of E than C1&C2 is, since C1 is more parsimonious. I call the version of Ockham's razor used here "the razor of silence." The better explanation of E is silent about C2; it does not deny that C2 was a cause. The problem changes if you consider two conjunctive hypotheses.

I disagree with the widely held view that it is metaphysical necessity, not nomological, that matters in the mind/body problem.