Socrates: The shoemaker, for example, uses a square tool, and a circular tool, and other tools for cutting? - Plato

When earth meets with fire and is dissolved by the keenness of it, it would drift about, whether it were dissolved in fire itself, or in some mass of air or water, until the parts of it meeting and again being united became earth once more; for it never could pass into any other kind. But when water is divided by fire or by air, it may be formed again and become one particle of fire and two of air: and the divisions of air may become for every particle broken up two particles of fire. And again when fire is caught in air or in waters or in earth, a little in a great bulk, moving amid a rushing body, and contending with it is vanquished and broken up, two particles of fire combine into one figure of air: and when air is vanquished and broken small, from two whole and one half particle one whole figure of water will be composed. Let us also reckon it once again thus: when any of the other kinds is intercepted in fire and is divided by it through the sharpness of its angles and its sides, if it forms into the shape of fire, it at once ceases from being divided...

Any one who has common sense will remember that the bewilderments of the eyes are of two kinds, and arise from two causes, either from coming out of the light or from going into the light

Philosophy is the highest music.