Well! that is true in a sense, as Socrates admits; not however in any sense which encourages idle acquiescence in what according to common language is our ignorance. There is a sense (it is exemplified in regard to sound and colour, perhaps in some far more important things) in which it is matter of experience that it is impossible to seek for, or be taught, what one does not know already. He who is in total ignorance of musical notes, who has no ear, will certainly be unaware of them when they light on him, or he lights upon them. Where could one begin? we ask, in certain cases where not to know at all means incapacity for receiving knowledge. Yes, certainly; the Pythagoreans are right in saying that what we call learning is in fact reminiscence- -: anamnêsis + famous word! and Socrates proceeds to show in what precise way it is impossible or possible to find out what you don't know: how that happens. In full use of the dialogue, as itself the instrument most [63] fit for him of whatever what we call teaching and learning may really be, Plato, dramatic always, brings in one of Meno's slaves, a boy who speaks Greek nicely, but knows nothing of geometry: introduces him, we may fancy, into a mathematical lecture-room where diagrams are to be seen on the walls, cubes and the like lying on the table--particular objects, the mere sight of which will rouse him when subjected to the dialectical treatment, to universal truths concerning them. The problem required of him is to describe a square of a particular size: to find the line which must be the side of such a square; and he is to find it for himself. Meno, carefully on his guard, is to watch whether the boy is taught by Socrates in any of his answers; whether he answers anything at any point otherwise than by way of reminiscence and really out of his own mind, as the reasonable questions of Socrates fall like water on the seed-ground, or like sunlight on the photographer's negative.