But if the rationalist is keen to make the mere faculty of thinking into a self subsisting being without any persisting intuition through which an object is given, merely because for him the unity of apperception in thinking allows explanation from something composite, instead admitting, as would be better to do, that he does not know how to explain the possibility of Reading nur with the fourth edition; earlier editions have undo in ihr, whose referent is presumably die Substanz; however, the context would appear to require the pronoun to be plural: in them (in ihnen), sc.