[48]. This principle was, I believe, first stated by Mr. De Morgan.
[49]. Not in every idea but only in the one so formulated.
[50]. [Note that this corollary is itself a theoretical inference and not an empirical rule.]
[51]. Popular Science Monthly, August, 1878.
[52]. [Later Pierce called it presumptive inference. See Baldwin’s Dictionary art. Probable Inference.]
[53]. This division was first made in a course of lectures by the author before the Lowell Institute, Boston, in 1866, and was printed in the Proceedings of the American Academy of Arts and Sciences, for April 9, 1867.
[54]. The Monist, January, 1891.
[55]. The neo-Darwinian, Weismann, has shown that mortality would almost necessarily result from the action of the Darwinian principle.
[56]. A feeling may certainly be compound, but only in virtue of a perception which is not that feeling nor any feeling at all.
[57]. [The reader will find further light on the following illustration in any text-book of projective geometry, e.g., Reye, Geometry of Position, I, pp. 17-24, or Encyc. Britannica, XI, p. 689.]