The Commens Dictionary

Quote from ‘Cambridge Lectures on Reasoning and the Logic of Things: Philosophy and the Conduct of Life’


Reasoning is of three kinds. The first is necessary, but it only professes to give us information concerning the matter of our own hypotheses and distinctly declares that, if we want to know anything else, we must go elsewhere. The second depends upon probabilities. The only cases in which it pretends to be of value is where we have, like an insurance company, an endless multitude of insignificant risks. Wherever a vital interest is at stake, it clearly says, “Don’t ask me.” The third kind of reasoning tries what il lume naturale, which lit the footsteps of Galileo, can do. It is really an appeal to instinct. Thus reason, for all the frills it customarily wears, in vital crises, comes down upon its marrow-bones to beg the succour of instinct.

CP 1.630
‘Il Lume Naturale’ (pub. 20.08.13-11:49). Quote in M. Bergman & S. Paavola (Eds.), The Commens Dictionary: Peirce's Terms in His Own Words. New Edition. Retrieved from
Aug 20, 2013, 11:49 by Mats Bergman
Last revised: 
Jan 07, 2014, 00:55 by Commens Admin