THEORY OF KNOWING.
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PROP. XVII.————
are not the substantial in cognition, because they cannot stand in cognition by themselves, or per se (Props. I. II.) The subject is not the substantial in cognition, because it cannot stand in cognition by itself, or per se (Prop. IX.) Therefore these are the phenomenal in cognition. But the synthesis of object-plus-subject is the substantial in cognition, because this, and this alone, will stand in cognition by itself, or per se. This alone can be known without anything more being known. The reader may thus perceive at a glance how flagrantly erroneous a system that must be which teaches (as all psychology does) a doctrine directly the reverse of this.
Substance and phenomenon originally bore the signification assigned to them here.14. There was, however, unquestionably a time when the terms of this distinction were kept in their proper places, and understood in their correct signification. Allowance being made (see Prop. X. Obs. 10) for the vagueness and ambiguity which pervade the older speculations, it may be confidently affirmed that Plato and his predecessors understood the terms substance and phenomenon in the retrieved sense which these Institutes have assigned to them. To bear out this assertion, we must show what the older philosophers understood by phenomenon and by substance: first, in reference to cognition; and, secondly, in reference to existence, although it is only in reference to the former
