Two things fill the mind with ever new and increasing admiration and awe, the oftener and more steadily we reflect on them: the starry heavens above and the moral law within.
Reason in a creature is a faculty of widening the rules and purposes of the use of all its powers far beyond natural instinct; it acknowledges no limits to its projects. Reason itself does not work instinctively, but requires trial, practice, and instruction in order gradually to progress from one level of insight to another.
For how is it possible, says that acute man, that when a concept is given me, I can go beyond it and connect with it another which is not contained in it, in such a manner as if that latter necessarily belonged to the former?
The means employed by Nature to bring about the development of all the capacities of men is their antagonism in society, so far as this is, in the end, the cause of a lawful order among men.
I learned to honor human beings, and I would find myself far more useless than the common laborer if I did not believe that this consideration could impart to all others a value establishing the rights of humanity.
Seek not the favor of the multitude; it is seldom got by honest and lawful means. But seek the testimony of few; and number not voices, but weigh them.
Human reason has this peculiar fate that in one species of its knowledge it is burdened by questions which, as prescribed by the very nature of reason itself, it is not able to ignore, but which, as transcending all its powers, it is also not able to answer.
Nature has willed that man should, by himself, produce everything that goes beyond the mechanical ordering of his animal existence, and that he should partake of no other happiness or perfection than that which he himself, independently of instinct, has created by his own reason.
The greatest problem for the human species, the solution of which nature compels him to seek, is that of attaining a civil society which can administer justice universally.