On Complementarity and Causal Isomorpism Douglas M. Snyder, Berkeley, California The Journal of Mind and Behavior , Winter 1988, Vol. 9, No. 1, Pages 1-4, ISSN 0271-0137 In a recent article, Kirsch and Hyland proposed that the notion of complementarity can be useful in understanding relations between mental and physical processes. Though this may be so,