Note 44 — Chapter XIV · THE STOIC PHILOSOPHY AS A WHOLE AND ITS HISTORICAL POSITION.
Oswald J. (Oswald Joseph) Reichel translation
The two tests of truth, proof and absence of refutation, do not, therefore, as Sextus expressly says, refer to the same cases. Our assumptions in respect of external appearances must be proved, before they can be allowed to be true; our impressions of the secret causes of these appearances must not be refuted. The former test applies to opinions regarding τὸ προσμένον; the latter, to opinions regarding τὸ ἄδηλον. Diog. 38. ↑