‘Logic’ (pub. 09.08.17-12:57). 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-logic-notebook-15.
Quote:
…logic is merely the science of ideas considered as signs.
Source:
Peirce, C. S. (1865-1909). The Logic Notebook. MS [R] 339.
URL:
http://www.commens.org/dictionary/entry/quote-logic-notebook-15