Bateson, Julian H. Bigelow, Warren McCulloch, Margaret Mead, F.S.C. Northrop, Walter Pitts, Arturo Rosenthbleuth, John Von Neumann, Claude Shannon, Heinz Von Foerster, W. Grey Walter, Norbert Wiener, and J.Z. Young. McCulloch, as Chairman, presided over the sessions and decided who to invite and what they should