‘Formal Logic’ (pub. 11.08.17-11:07). Quote in M. Bergman & S. Paavola (Eds.), The Commens Dictionary: Peirce's Terms in His Own Words. New Edition. Retrieved from http://www.commens.org/dictionary/entry/quote-material-logic-0.
Quote:
Formal logic classifies arguments by producing forms in which, the letters of the alphabet being replaced by any terms whatever, the result will be a valid, probable, or sophistic argument, as the case may be…
Source:
Peirce, C. S. (1902). Material Logic. In J. M. Baldwin (Ed.), Dictionary of Philosophy and Psychology, Vol. II (pp. 44-45). London: Macmillan and Co.
URL:
http://www.commens.org/dictionary/entry/quote-material-logic-0