The Commens Dictionary
Quote from ‘CSP's Lowell Lectures of 1903. 2nd Part of 3rd Draught of Lecture III’
I will, however, make a few remarks on these categories. By way of preface, I must explain that in saying that the three, Firstness, Secondness, and Thirdness, complete the list, I by no means deny that there are other categories. On the contrary, at every step of every analysis, conceptions are met with which presumably do not belong to this series of ideas.