 Brentano requires from a theory of judgement that it stays away from postulating fictitious entities of any kind. In this respect his earlier analysis of propositions of the O-form and the A-form turns out to be deficient. His claim about the O-form was that in judging that S is not P, one affirms the existence of an S-that-is-not-P. That conflicts with his restriction against negative properties because when one affirms a complex like S-that-is-not-P, one affirms all of its parts (see PES 208 [II 49; SVS 1, 231]). Thus, in affirming an S-that-is-not-P, one would affirm not only the entire complex, but also both of its “parts”: S and not-P. Note that the problem cannot be solved by joining the negation with the copula “is”, because the copula indicates the quality of the judgement and propositions of the O-form express positive judgements according to Brentano.