The Commens Dictionary
Quote from ‘Minute Logic: Chapter II. Section II. Why Study Logic? ’
Now a person cannot perform the least reasoning without some general ideal of good reasoning; for reasoning involves deliberate approval of one’s reasoning; and approval cannot be deliberate unless it is based upon the comparison of the thing approved with some idea of how such a thing ought to appear. Every reasoner, then, has some general idea of what good reasoning is. This constitutes a theory of logic: the scholastics called it the reasoner’s logica utens. Every reasoner whose attention has been considerably drawn to his inner life must soon become aware of this.
‘Logica Utens’ (pub. 01.02.13-18:11). 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-minute-logic-chapter-ii-section-ii-why-study-logic-0.