To Florus 3.32
Suppose, for example, the question concerns Goliath’s complexion, and one person insists he was black and another that he was white (compare 1 Samuel 17:4–5). These opposing opinions can both be false, but they cannot both be true. It cannot be true that he was black if he was always white, or that he was white if he remained black throughout his life. Thus these two opinions, which cannot both be true, can both be false if his complexion was neither white nor black but tawny—or a moderate blend of the opposites, with whiteness softened but no full blackness introduced. Differing and opposed descriptions can therefore be denied together more readily than affirmed together.
But opposites without a middle, such as good and evil, just and unjust, innocence and guilt, cannot coexist at one time in one and the same subject; so affirming either necessarily denies the other. For example, a command, advice, or assistance cannot be both just and unjust at the same time. Equally, a person cannot at one and the same time be both guilty and innocent, both good and evil.
Latin
Veniat verbi gratia in quaestionem Golias quo fuerit affectus colore, et unus eum nigrum, alter candidum fuisse confirmet [n37] ; diversa haec opinio potest utraque falsa, utraque autem vera esse non potest. Non enim potest verum esse nigrum illum fuisse, si candidus fuit semper, aut candidum fuisse, si niger omni aetate permansit. Haec ergo utraque opinio, quae simul vera esse non potest, simul falsa esse hoc modo potest, si nec candidus nec niger, sed flavus eius color fuit vel infracto candore nec tamen infusa nigredine ex contrariis mediocriter temperatus. Facilius ergo res diversae et contrariae negari possunt pariter quam pariter approbari. Ista autem contraria, quae medium non habent, ut puta bonum et malum, iustum et iniustum, innocentia et reatus, ut uno tempore in unum atque idem convenire non possunt, ita necesse est, ut altero eorum posito alterum denegetur, id est, ut vel praeceptum vel consilium vel adiumentum non potest simul in uno tempore et iustum et iniustum esse, ita et homo non potest uno eodemque tempore et reus et innocens et bonus et malus esse.