The Commens Dictionary
Quote from ‘Minute Logic: Chapter II. Prelogical Notions. Section I. Classification of the Sciences (Logic II)’
…a natural class [is] a family whose members are the sole offspring and vehicles of one idea, from which they derive their peculiar faculty…
EP 2:125; CP 1.222
‘Natural Class’ (pub. 28.07.15-10:56). 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-prelogical-notions-section-i-classification-scienc-36.