Note 33 — Chapter XIV · THE STOIC PHILOSOPHY AS A WHOLE AND ITS HISTORICAL POSITION.

(2) Notions. This going beyond sensation becomes, however, a necessity. By a repetition of the same perception a notion (πρόληψις) arises. A notion, therefore, is nothing else than the general picture retained in the mind of what has been perceived.33 On these notions retained by memory depend all speaking and thinking. They are what commonly go under the name of things; and speech is only a means of recalling definite perceptions34 to the memory. Notions are presupposed in all scientific knowledge.35 Together with sensations they form the measure of the truth of our convictions;36 and it holds true of them as it did of sensations—that they are true in themselves and need no proof.37 Taken by themselves, notions, like perceptions, are reflections in the soul of things on which the transforming action of the mind, changing external impressions into conceptions, has not as yet been brought to bear.