dualism, ethical See ZOROASTRIANISM. Ducasse, C(urt) J(ohn) (1881–1969), Frenchborn American philosopher of mind and aesthetician. He arrived in the United States in 1900, received his Ph.D. from Harvard (1912), and taught at the University of Washington (1912–26) and Brown University (1926–58). His most important work is Nature, Mind and Death (1951). The key to his general theory is a non-Humean view of causation: the relation of causing is triadic, involving (i) an initial event, (ii) the set of conditions under which it occurs, and (iii) a resulting event; the initial event is the cause, the resulting event is the effect. On the basis of this view he constructed a theory of categories – an explication of such concepts as those of substance, property, mind, matter, and body. Among the theses he defended were that minds are substances, that they causally interact with bodies, and that human beings are free despite every event’s having a cause. In A Critical Examination of the Belief in a Life after Death (1961), he concluded that ‘the balance of the evidence so far obtained is on the side o. . . survival.’ Like Schopenhauer, whom he admired, Ducasse was receptive to the religious and philosophical writings of the Far East. He wrote with remarkable objectivity on the philosophical problems associated with so-called paranormal phenomena. Ducasse’s epistemological views are developed in Truth, Knowledge and Causation (1968). He sets forth a realistic theory of perception (he says, about sense-qualities, ‘Berkeley is right and the realists are wrong’ and, of material things, ‘the realists are right and Berkeley is wrong’). He provides the classical formulation of the ‘adverbial theory’ or sense-qualities, according to which such qualities are not objects of experience or awareness but ways of experiencing or of being aware. One does not perceive a red material object by sensing a red sense-datum; for then perceiving would involve three entities – (i) the perceiving subject, (ii) the red sense-datum, and (iii) the red material object. But one may perceive a red material object by sensing redly; then the only entities involved are (i) the perceiving subject and (ii) the material object. Ducasse observes that, analogously, although it may be natural to say ‘dancing a waltz,’ it would be more accurate to speak of ‘dancing waltzily.’ See also PERCEPTION , PHILOSOPHY OF MIN. R.M.C.