True wisdom is less presuming than folly. The wise man doubteth often, and changeth his mind; the fool is obstinate, and doubteth not; he knoweth all things but his own ignorance.
Special care should be taken of the health of the inhabitants, which will depend chiefly on the healthiness of the locality and of the quarter to which they are exposed, and secondly on the use of pure water; this latter point is by no means a secondary consideration. For the elements which we use the most and oftenest for the support of the body contribute most to health, and among those are water and air. Wherefore, in all wise states, if there is want of pure water, and the supply is not all equally good, the drinking water ought to be separated from that which is used for other purposes.
Everyone can recognize history when it happens. Everyone can recognize history after is has happened; but only the wise man knows at the moment what is vital and permanent, what is lasting and memorable.
Not to converse with a man worthy of conversation is to waste the man. To converse with a man not worthy of conversation is to waste words. The wise waste neither men nor words.
When your weapons are dulled and ardour damped, your strength exhausted and treasure spent, neighboring rulers will take advantage of your distress to act. And even though you have wise counsellors, none will be able to lay good plans for the future. Thus, while we have heard of blundering swiftness in war, we have not yet seen a clever operation that was prolonged.
Some princes, so as to hold securely the state, have disarmed their subjects, others have kept their subject towns distracted by factions...Our forefathers, and those who were reckoned wise, were accustomed to say that it was necessary to hold Pistoia [an Italian city] by factions and Pisa by fortress, and with this idea they fostered quarrels in some of their tributary towns so as to keep possession of them the more easily.
I would not say that old men grow wise, for men never grow wise; and many old men retain a very attractive childishness and cheerful innocence. Elderly people are often much more romantic than younger people, and sometimes even more adventurous, having begun to realize how many things they do not know.
I learned from my illiterate but wise mother that all rights to be deserved and preserved came from duty well done. Thus the very right to live accrues to us only when we do the duty of citizenship of the world. From this one fundamental statement, perhaps it is easy enough to define the duties of Man and Woman and correlate every right to some corresponding duty to be first performed. Every other right can be shown to be a usurpation hardly worth fighting for.
I told you that your dream was a difficult one. It's the simple things in life that are the most extraordinary; only wise men are able to understand them.
That the world is not the embodiment of an eternal rationality can be conclusively proved by the fact that the piece of the worldthat we know--I mean our human reason--is not so very rational. And if it is not eternally and completely wise and rational, then the rest of the world will not be either; here the conclusion a minori ad majus, a parte ad totum applies, and does so with decisive force.