From this I conclude that the best education for the situations of actual life consists of the experience we acquire from the study of serious history. For it is history alone which without causing us harm enables us to judge what is the best course in any situation or circumstance.

Monarchy degenerates into tyranny, aristocracy into oligarchy, and democracy into savage violence and chaos.

In our own time the whole of Greece has been subject to a low birth rate and a general decrease of the population, owing to which cities have become deserted and the land has ceased to yield fruit, although there have neither been continuous wars nor epidemics...For as men had fallen into such a state of pretentiousness, avarice, and indolence that they did not wish to marry, or if they married to rear the children born to them, or at most as a rule but one or two of them, so as to leave these in affluence and bring them up to waste their substance, the evil rapidly and insensibly grew.

When the ancients said a work well begun was half done, they meant to impress the importance of always endeavoring to make a good beginning.

Those who know how to win are much more numerous than those who know how to make proper use of their victories.

That historians should give their own country a break, I grant you; but not so as to state things contrary to fact. For there are plenty of mistakes made by writers out of ignorance, and which any man finds it difficult to avoid. But if we knowingly write what is false, whether for the sake of our country or our friends or just to be pleasant, what difference is there between us and hack writers? Readers should be very attentive to and critical of historians, and they in turn should be constantly on their guard.

The particular aspect of history which both attracts and benefits its readers is the examination of causes and the capacity, which is the reward of this study, to decide in each case the best policy to follow. Now in all political situations we must understand that the principle factor which makes for success or failure is the form of a state's constitution: it is from this source, as if from a fountainhead, that all designs and plans of action not only originate but reach their fulfillment.