The American Humanist Association is the custodian of a document series that has, three times in ninety years, tried to write down what humanists collectively think, and whose successive revisions are a more honest record of the movement's history than any narrative would be.
Humanist Manifesto I appeared in 1933, drafted by Roy Wood Sellars and Raymond Bragg and signed by thirty-four people including John Dewey. Its striking feature, usually forgotten, is that it describes humanism as a religion: a religious humanism, with the supernatural removed and the framework retained. It was also, in 1933, extremely optimistic about human progress.
Humanist Manifesto II, in 1973, opens by saying so. Its authors, Paul Kurtz and Edwin Wilson, described the first as far too optimistic in the light of Nazi atrocities and the war, and wrote a longer and soberer document containing the line for which it is remembered: no deity will save us, we must save ourselves.
Humanist Manifesto III, in 2003, is shorter than either and much less prescriptive, and was signed by more than twenty Nobel laureates.
The Association itself was founded in 1941, eight years after the first manifesto, out of the network of humanist fellowships that produced it. It is a nonprofit educational body with no initiation and no membership requirement beyond joining, and it works through more than two hundred and fifty local affiliates.
The word manifesto was chosen deliberately, and the documents read as manifestos: they state positions rather than argue for them, which is the point at which even sympathetic critics have found them thin.