Inever govern myself, no rational man ever did govern himself, by abstractions and universals. I do not put abstract ideas wholly out of any question; because I well know that under that name I should dismiss principles, and that without the guide and light of sound, well-understood principles, all reasonings in politics, as in everything else, would be only a confused jumble of particular facts and details, without the means of drawing out any sort of theoretical or practical conclusion. A statesman differs from a professor in an university: the latter has only the general view of society; the former, the statesman, has a number of circumstances to combine with those general ideas, and to take into his consideration. Circumstances are infinite, are infinitely combined, are variable and transient: he who does not take them into consideration is not erroneous, but stark mad; dat operam ut cum ratione insaniat; he is metaphysically mad. A statesman, never losing sight of principles, is to be guided by circumstances; and judging contrary to the exigencies of the moment, he may ruin his country forever.