Phaedo.But this is impossible if our soul did not exist somewhere before being born in this human form; and so by this argument also it appears that the soul is immortal.But, Cebes, said Simmias, what were the proofs of this? Remind me; for I do not recollect very well just now.Briefly, said Cebes, a very good proof is this: When people are questioned, if you put the questions well, they answer correctly of themselves about everything; and yet if they had not within them some knowledge and right reason, they could not do this. And that this is so is shown most clearly if you take them to mathematical diagrams or anything of that sort.And if you are not convinced in that way, Simmias, said Socrates, see if you don’t agree when you look at it in this way. You are incredulous, are you not, how that which is called learning can be recollection?I am not incredulous, said Simmias, but I want just what we are talking about, recollection. And from what Cebes undertook to say I already begin to recollect and be convinced; nevertheless, I should like to hear what you were going to say.It was this, said he. We agree, I suppose, that if anyone is to remember anything, he must know it at some previous time?Certainly, said he.Then do we agree to this also, that when knowledge comes in such a way, it is recollection? What I mean is this: If a man, when he has heard or seen or in any other way perceived a thing, knows not only that thing, but also has a perception of some other thing, the knowledge of which is not the same, but different, are we not right in saying that he recollects the thing of which he has the perception?What do you mean?Let me give an example. Knowledge of a man is different from knowledge of a lyre.Of course.Well, you know that a lover when he sees a lyre or a cloak or anything else which his beloved is wont to use, perceives the lyre and in his mind receives an image of the boy to whom the lyre belongs, do you not? But this is recollection, just as when one sees Simmias, one often remembers Cebes, and I could cite countless such examples.To be sure you could, said Simmias.Now, said he, is that sort of thing a kind of recollection? Especially when it takes place with regard to things which have already been forgotten through time and inattention?Certainly, he replied.Well, then, said Socrates, can a person on seeing a picture of a horse or of a lyre be reminded of a man, or on seeing a picture of Simmias be reminded of Cebes?Surely.