Democracy in America, Volume 2 by Alexis de Tocqueville

Equality suggests to the human mind several ideas which would not have originated from any other source, and it modifies almost all those previously entertained. I take as an example the idea of human perfectibility, because it is one of the principal notions that the intellect can conceive, and because it constitutes of itself a great philosophical theory, which is every instant to be traced by its consequences in the practice of human affairs. Although man has many points of resemblance with the brute creation, one characteristic is peculiar to himself-he improves: they are incapable of improvement. Mankind could not fail to discover this difference from its earliest period. The idea of perfectibility is therefore as old as the world; equality did not give birth to it, although it has imparted to it a novel character.

When the citizens of a community are classed according to their rank, their profession, or their birth, and when all men are constrained to follow the career which happens to open before them, everyone thinks that the utmost limits of human power are to be discerned in proximity to himself, and none seeks any longer to resist the inevitable law of his destiny. Not indeed that an aristocratic people absolutely contests man's faculty of self-improvement, but they do not hold it to be indefinite; amelioration they conceive, but not change: they imagine that the future condition of society may be better, but not essentially different; and whilst they admit that mankind has made vast strides in improvement, and may still have some to make, they assign to it beforehand certain impassable limits. Thus they do not presume that they have arrived at the supreme good or at absolute truth (what people or what man was ever wild enough to imagine it? )