cession of minimal intervals or immediate judgements. The connexion of D with A will then be manifest as the inevitable conclusion of the self-evident connexion of D with C, of C with B, and of B with A. To demonstrate the necessary connexion of D with A is thus to analyse the 'stretch' between them into the indivisible, elementary 'stretches'[1] of which it is composed. These simple or indivisible intervals (the judgements A-B, B-C, C-D) are the primary, self-evident, and yet; necessary truths, the immediate premisses, which the proof that A must be D presupposes as its logical foundations.
Such self-evident and yet necessary truths correspond to the 'simple propositions' or 'simple ideas' which, according to Descartes, are the intuitively apprehended data of all our knowledge. The human intellect, he maintains, is infallible in the exercise of the two functions which express its own nature—infallible in its acts of 'intuition', and infallible in its inferential movement.[2] Thus, I can apprehend the necessary, but immediate, implication of the two elements in a self-evident datum or 'simple proposition'. I can 'see', e. g., that '2+2=4'. and that 'my self-consciousness involves my existence', And, by an unbroken inferential progress from self-evident to self-evident, my intellect can move to the infallible apprehension of a mediate necessary truth.
