The reason is this: Learning things gives great pleasure not only to philosophers but also in the same way to all other men, though they share this pleasure only to a small degree. The reason why we enjoy seeing likenesses is that, as we look, we learn and infer what each is, for instance, that is so and so. If we have never happened to see the original, our pleasure is not due to the representation as such but to the technique or the color or some other such cause. We have, then, a natural instinct for representation and for tune and rhythm It is not clear wheter the two general causes are (1) the instinct for imitation, (2) the natural enjoyment of mimicry by others; or whether these two are combined into one and the second cause is the instinct for tune and rhythm. Obviously this last is an essential cause of poetry. —for the metres are obviously sections of rhythms e.g., the rhythm of the blacksmith’s hammer or of a trotting horse is dactylic, but the hexameter is a section or slice of that rhythm; it is cut up into sixes. —and starting with these instincts men very gradually developed them until they produced poetry out of their improvisations. Poetry then split into two kinds according to the poet’s nature. For the more serious poets represented fine doings and the doings of fine men, while those of a less exalted nature represented the actions of inferior men, at first writing satire just as the others at first wrote hymns and eulogies.