Note 369 — Chapter III

Lambert is usually regarded as the originator of the idea of framing dicta that shall be directly applicable to figures other than the first. Thomson, however, points out that it is an error to suppose that Lambert was the first to invent such dicta. “More than a century earlier, Keckermann saw that each figure had its own law and its own peculiar use, and stated them as accurately, if less concisely, than Lambert” (Laws of Thought, p. 173, note). Distinct principles for the second and third figures are laid down also in the Port Royal Logic, which was published in 1662.