 The parts in italics are the tacit assumptions that Brentano makes in this argument. Anyone who takes the subject matter of judgements to be propositions would deny them and hence the soundness of the argument. That would not immediately disprove the reduction  claim (6),  but it would deprive Brentano of a good reason for introducing an asymmetry into his translation schemes. Because of this problem, it seems questionable whether Brentano’s reduction project in the third part of his theory succeeds. Apparently, Brentano himself changed his mind on the validity of his argument when he later developed his theory of double judgement (see  section 5  below). That means that he no longer can make use of his initial argument to show that “existence” has no meaning by itself.