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positions cannot be brought under the subject-predicate form. Identity propositions, like this is that man,' cannot be construed according to the subject-predicate relation. These propositions do not express any relation between two things, but the simple identity of a thing with itself. We cannot say here that 'that man 'is the predicate or adjective of this man. These are non-relational and therefore non-predicative propositions. Russell' also opposes the view that all propositions are reducible to the subject-predicate form. He thinks that the propositions which assign the qualities of things come under this form, e.g. " this tbing is round, and red and so on ” On the other hand, the propositions which express relations cannot be reduced to the subject-predicate form Thus in the propositions 'A 18 like B,' ' B is the brother of C,' 'C is greater than D,' we cannot say that the terminal term is predicated of the initial term. They express respectively a symmetrical, a non-symmetrical and an asymmetrical relation between different terms, of which one cannot be regarded as the quality of the other
When we consider the different views about the import of propositions, we are led to think that a distinction should be made between predicative and non-predicative propositions. In a predicative proposition a subject is related to a predicate as substantive to adjective. All propositions, however, are not predicative in this sense There are many propositions which cannot be brought under the subjectpredicate form. Thus Russell's relational propositions, ' A is like B,''C is greater than D,' do not conform to the subject-predicate form. It may be said that these propositions are predicative because in the one likeness to B'is predicated of A, and in the other 'being greater than D'
1 Our Knowledge of the External World, pp. 45-50,
