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.

In man (as the only rational creature on earth) those natural capacities which are directed to the use of his reason are to be fully developed only in the race, not in the individual.

Freedom is that faculty that enlarges the usefulness of all other faculties.

By a lie, a man... annihilates his dignity as a man.

How then is perfection to be sought? Wherein lies our hope? In education, and in nothing else.

In every department of physical science there is only so much science, properly so-called, as there is mathematics.

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 me and the moral law within me.