5
Todhunter’s Plane Co-ordinate Geometry, chap. ii. pp. 11–14.
6
An explanation of this and other technical terms of the old logic will be found in my Elementary Lessons in Logic, Sixth Edition, 1876; Macmillan.
7
Elementary Lessons in Logic, pp. 67, 79.
8
Pure Logic, p. 19.
9
An Outline of the Necessary Laws of Thought, Fifth Ed. p. 161.