The Commens Dictionary

Quote from ‘The Fourth Curiosity’


A character which is not sometimes true and sometimes false of the same singular is a kind. A kind may not exist at all; or it may exist in but one sole singular, which the old logics used to say was the case with the kind called sun. [—]

I consider a kind to be an ens rationis, although that may be open to dispute, at least as regards some kinds; but there can, I think, be no doubt that a class is an ens rationis. For a class, unlike a kind, is not a character, but is the totality of all those singulars that possess a definite existent character, which is the essential character of the class.

CP 4.647-8
‘Kind’ (pub. 07.03.16-13:50). Quote in M. Bergman & S. Paavola (Eds.), The Commens Dictionary: Peirce's Terms in His Own Words. New Edition. Retrieved from
Mar 07, 2016, 13:50 by Mats Bergman
Last revised: 
Mar 07, 2016, 13:53 by Mats Bergman