1. the questionable assumption that all human phenomena, including rationality, culture, and ethics, can be explained with reference to strictly biological processes. In this sense, the biological fallacy is one of naturalistic reductionism. 2. in the controversial view of some ecological theorists, the “fallacy” of equating life with the life of individual organisms. The term implies that the vital force referred to as “life” is better understood as inherent in, or as a quality of, the totality of the ecosystem.