peculiar knowledge, hence we may be deceived about them, yet not after a contrary manner, but while possessing the universal, yet are deceived in the particular. It is the same also as to what we have spoken of, for the deception about the middle is not contrary to science about syllogism, nor the opinion as to each of the middles. Still nothing prevents one who knows that A is with the whole of B, and this again with C, thinking that A is not with C, as he who knows that every mule is barren, and that this (animal) is a mule, may think that this is pregnant; for he does not know that A is with C from not at the same time surveying each. Hence it is evident that if he knows one (of the propositions), but is ignorant of the other, he will be deceived as to how the universal subsists with reference to the particular sciences. For we know nothing of those things which fall under the senses as existent apart from sense, not even if we happen to have perceived it before, unless in so far as we possess universal and peculiar knowledge, and not in that we energize. For to know is predicated triply, either as to the universal or to the peculiar (knowledge), or as to energizing, so that to be deceived is likewise in as many ways. Nothing therefore prevents a man both knowing and being deceived about the same thing, but not in a contrary manner, and this happens also to him, who