 This distinction motivates different versions of non-reductive physicalism. On one interpretation, the non-reductive physicalist opposes the idea that we can and should in fact reduce high-level sciences; we need them for epistemic or pragmatic purposes (Fodor 1974, 1997; Putnam 1978; Van Gulick 1992). We need a plurality of autonomous theories and frameworks. However, the non-reductive physicalist accepts that what is actually out there might very well be all of one kind, at least in some ultimate sense such that ontological reductionism is true.