In this century there has hardly been a group of philosophers more shrouded in misunderstandings and prejudices than the Vienna Circle. (This is best summed up in Passmore's verdict of 1968: "Logical positivism, then, is dead as a philosophical movement ever becomes".)¹ After a long slumber this movement is presently experiencing a reawakening of historical interest in its main protagonists and ideas. Critical reassessment was spurred by the edition of the Vienna Circle Collection (eds. H.L. Mulder, R.S. Cohen, B. McGuinness, Reidel/Kluwer Dordrecht, 1974ff.), followed by the publication of the contributions to the 3rd International Wittgenstein Symposium 1978 (Berghel, Hübner, Köhler, 1979). Several years ago a series of writings on the Vienna Circle and Logical Empiricism was initiated (Wiener Kreis — Schrien zum Logischen Empirismus, eds. H.L. Mulder, R.S. Cohen, B. McGuinness, R. Hegselmann, A.J. Kox, F. Stadler, Suhrkamp, Frankfurt 1986ff.).²