Reply #12: Logical Positivism (logical empiricsm) came out of the Vienna Circle in the 1930's.

[humblebum]

It is also the basis for The Scientific Method and over several decades it was adapted by almost all disciplines,most notably the hard and soft sciences and the legal profession, after modifications of course. It was the most widely used epistemology by scholars up through the 1970's and has gradually been largely replaced by more integrated epistemologies. Several famous atheists besides Ayer were and are, by admission, logical positivists ie. B. Russell and Stephen Hawking.