 Up until the 1950s, there were no active research programs that were looking for the innate factors in knowledge and cognition that had been hypothesized and argued for by Nativist thinkers since Plato. It was widely agreed that the centuries-old battles between Empiricists and Nativists were over, and that the Empiricists had decisively won. The Nativist situation was actually worse than that: innateness claims were seen as not only wrong, but as ultimately unscientific approaches to mind and perhaps incoherent as well.  The prevailing research agenda for scientists and philosophers interested in how the mind works was to show how our knowledge and abilities could be fully accounted for on the basis of our sensory experiences and the general learning mechanisms that operate on them. 