INTRODUCTION The present volume unites contributions by the leading figure of the Vienna Circle and by two of his closest assoCiates, contributions that deal with an area of thought represented, indeed, in this Collection but certainly not the central one in the common picture ofthe Circle's activities. It is no accident that an interest in ethics and the philosophy of action was particularly marked in what Neurath was apt to call the right wing of the Circle. For them, as for Wittgenstein (the respected mentorofSchlickandWaismanninparticular), theadvancetobehoped for in philosophy consisted...