The Commens Dictionary
Quote from ‘A Syllabus of Certain Topics of Logic’
Science of Discovery is either, I. Mathematics; II. Philosophy; or III. Idioscopy.
Mathematics studies what is and what is not logically possible, without making itself responsible for its actual existence. Philosophy is positive science, in the sense of discovering what really is true; but it limits itself to so much of truth as can be inferred from common experience. Idioscopy embraces all the special sciences, which are principally occupied with the accumulation of new facts.
‘Mathematics’ (pub. 05.02.13-20:10). 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-syllabus-certain-topics-logic-3.