Leibniz, id., pag

Cui singula insunt, etiam ex ipsis constitutum inest. Si a est in c et b est in c etiam a -+- 5 erit in c .

22. Boole, Math. anaLj pag. 16; The laïcs of thought, pag. 33.

24-29. Ch. Peirce^ Three papers 07i Logic, Journal of j^peculative Philosophy, a. 1868; American Journal of Math., t. 3, a. 1880.

Notes — 1 129

ScBRODER, Algebra der Logik, t. I, a. 1890, p. 362, 382; t. Il, a.