The primary indication, to my thinking, of a well-ordered mind is a man's ability to remain in one place and linger in his own company. You must linger among a limited number of master thinkers, and digest their works, if you would derive ideas which shall win firm hold in your mind. Everywhere means nowhere.
Our motto,1 as you know, is "Live according to Nature"; but it is quite contrary to nature to torture the body, to hate unlaboured elegance, to be dirty on purpose, to eat food that is not only plain, but disgusting and forbidding. 5. Just as it is a sign of luxury to seek out dainties, so it is madness to avoid that which is customary and can be purchased at no great price.
Philosophy calls for plain living, but not for penance; and we may perfectly well be plain and neat at the same time. This is the mean of which I approve; our life should observe a happy medium between the ways of a sage and the ways of the world at large; all men should admire it, but they should understand it also.
Associate with those who will make a better man of you. Welcome those whom you yourself can improve. The process is mutual; for men learn while they teach.
Seneca: Letters from a Stoic (and Biography) [Annotated]