Irreducible ( philosophy ) Irreducibility , in philosophy , has the sense that a complete account of an entity will not be possible at lower levels of explanation and which has novel properties beyond prediction and explanation . Another way to state this is that Occam 's razor requires the elimination of only those entities that are unnecessary , not as many entities as could conceivably be eliminated . Lev Vygotsky provides the following illustration of the idea , in his Thought and Language : `` Two essentially different modes of analysis are possible in the study of psychological structures . It seems to us that one of them is responsible for all the failures that have beset former investigators of the old problem , which we are about to tackle in our turn , and that the other is the only correct way to approach it . The first method analyzes complex psychological wholes into `` elements `` . It may be compared to the chemical analysis of water into hydrogen and oxygen , neither of which possesses the properties of the whole and each of which possesses properties not present in the whole . The student applying this method in looking for an explanation of some property of water — why it extinguishes fire , for example — will find to his surprise that hydrogen burns and oxygen sustains fire ... . In our opinion the right course to follow is to use the other type of analysis , which may be called `` analysis into units '' . By `` unit '' , we mean a product of analysis which , unlike elements , retains all the basic properties of the whole , and which cannot be further divided without losing them . Not the chemical composition of water , but its molecules and their behaviour , are the key to the understanding of the properties of water ... `` In other words : to conserve the properties under investigation , it is necessary to remain within a certain level of complexity . Irreducibility is most often deployed in defence of the reality of human subjectivity and/or free will , against those who treat such things as folk psychology , such as Paul and Patricia Churchland . See also Emergent property References Thought and Language Categories : Reductionism 