We have both spoken, in this interminable thread, of the necessity for falsifiability in scientific hypotheses. This was Karl Popper's view. Later Philosophers of science took a different view, saying that sciences, like taxonomy, didn't seem a good fit with Popper's dfn (recent views of taxonomy, which study cladistics and genetic of lumped together genera have claimed that it is falsifiable and split genera).
The most recent definition seen, about 20-25 years ago (Feyraband, some name like that) said that Science is what scientists do. This seemed to be somewhat circular to me!
