Things are always meeting each other and being affected by each other. Things are always changing.

Things can be divided into those that have pleasure or pain and those that haven’t; that is, into alive and not alive things. There is no pleasure or pain without thought. And there is no pleasure or pain without some feeling, by the object having it, of what it is and what it can be.

A dry bit of bark moves in the wind. A frog moves. The dry bit of bark moves because a force big enough makes it move, and the force is from the outside. The frog is also affected by the wind, but in a calm day, a quiet day, it can move by a force from itself. The reason it moves is because something in it, in touch with the frog’s possibilities, or what it wants, says it is good to move that way. And the frog will go towards things, or away from things; and this shows there is pleasure or pain in it, for pleasure is that which shows a thing at one with something else; and pain is that which shows a thing not at one with something else.

The frog, in remaining on the grass, or jumping away from the grass, shows it has some state of frog and grass in it, and has pleasure or pain about it. For the frog to leave grass or stay on grass means that grass, however incompletely, is affecting the frog, that is, is in the frog. For the frog shows a state arising from itself, of pleasure or pain as to the grass. The bit of dry bark may move about on the grass, but not because of a state in itself as to the grass: it moves because the wind moves it.

Now if a frog has pleasure and pain about things, it is impelled, in order to have as little frog discontent as possible and as much frog content as possible, to have in it something of what the things making for discontent or content are. It pays a frog to be right as to grass, water, mud, stones, leaves on water, and so on. Sometimes it must be particularly right as to a sound and mud and a stone. Here the frog has thought about these things; the frog has gone after these things; and the frog has got these things into itself: something, at least, of what these things are. Thought begins this way, and never changes entirely, however complicated it is, in an Aristotle, or a Kant, or an Edison, or a Max Beerbohm.