[Note] that in the soul there is hope of what is expected, perception of what is present, and memory of what is absent.[1]
Concerning memory. [Note] that the soul will have nothing that came to it from combination with the body, such as thinking. So it does not remember, either. For when its knowledge is slipping away and it requires memory for the retention of what was known, but then knowledge does not have a before and an after, except for handling the theoretical issues, but it always stands firm and is examined in the now. And after the body, since [the soul] stands firm and applies knowledge to the same things, it does not require memory. For the retention of what was known long ago is memory.[2]
Memory is a state capable of retaining a belief.[3] Aristotle established certain topics in On memory and On sleep and On divination in sleep, [topics] through which recollecting [derives] not only from the contraries but also from what is similar, and from some other [types] of thing. For these topics become causes of recollecting for us. For through contraries, so to speak, [i.e.] by passing directly over into what has been said of the contraries, we recollect this: from bitter, sweet; from white, black; from cold, heat.
[Note] that there are three parts of readiness in learning: tight-witted, memory, acuity. Memory is the preservation of what one learned; acuity is the swiftness of thought; tight-witted is from something which one has learned searching out also what one has not [yet] learned.[4]