The words of Mr. Lewontin at the top of this thread reveal him to be a shoddy scientist. The greatest discoveries of sicience have always been presented as theories whether we are talking about the theory of gravity, the theory of evolution, or the theory of relativity. It’s part of the scientific sense of inquiry, integrity, and humility that all so-called knowledge is theoretical and that if, in the future, evidence reveals that what we assumed is true proves to be false, then we will gladly change our theory. Newton’s theory of motion was considered unassailable for hundreds of years until Einstein came along and proved him wrong.