We do not say with Descartes: “Cogito, ergo sum,” . . . ; on the contrary, instead of basing ourselves immediately upon the operation which is proper to the highest of our faculties, we rest first of all and with great assurance in the experience of touching, in which we have at the same time an experience of existing. To be sure, this consciousness is not without thought, but it is a thought which depends upon touch and which does not as yet reveal itself as thought. It is the tangible qualities which are to us first principles of thought and action. If we had to venture an Aristotelian counterpart to Descartes’ “Cogito, ergo sum,” we would say without hesitation: “Sedeo, ergo sum”: I am sitting, therefore I am.
Charles De Koninck, “«Sedeo, Ergo Sum»: Considerations on the Touchstone of Certitude,” Laval Théologique et Philosophique 6, no. 2 (1950): 343–48.