The Commens Dictionary

Quote from ‘Grand Logic 1893: Division III. Substantial Study of Logic Chapter VI. The Essence of Reasoning’


St. Thomas Aquinas [Summa totius logicæ Aristotelis (Opusculum 48)] divides the operations of the Understanding in reference to the logical character of their products into
     Simple Apprehension,
     Judgment, and
     Ratiocination, or Reasoning. [—]

Ratiocination or reasoning produces inferences or reasonings, which are expressed by argumentations, as, ” I think, therefore I must exist,” “Enoch, being a man, must have died; and since the Bible says he did not die, not everything in the Bible can be true.”

CP 4.38-39
‘Ratiocination’ (pub. 03.02.13-09:34). Quote in M. Bergman & S. Paavola (Eds.), The Commens Dictionary: Peirce's Terms in His Own Words. New Edition. Retrieved from
Feb 03, 2013, 09:34 by Sami Paavola
Last revised: 
Jan 07, 2014, 01:00 by Commens Admin