Kitap 2
17
Throwing away, then, I say, this self-conceit, by which we fancy we have gained some knowledge of what is useful, we should come to philosophic reasoning as we do to mathematics and music; otherwise we shall be far from making any improvement, even if we have read over all the compends and commentaries, not only of Chrysippus, but of Antipater, and Archedemus too.
How to deal with the semblances of things.
18
Every habit and faculty is preserved and increased by correspondent actions; as the habit of walking, by walking; of running, by running. If you would be a reader, read; if a writer, write. But if you do not read for a month together, but do something else, you will see what will be the consequence. So after sitting still for ten days, get up and attempt to take a long walk, and you will find how your legs are weakened. Upon the whole, then, whatever you would make habitual, practise it; and if you would not make a thing habitual, do not practise it, but habituate yourself to something else.
