It is a truth of no little importance to us in our present situation, not only that the manners of a people are of consequence to the liability of every civil society, but that they are of much more consequence to free states, than to those of a different kind. In many of these last, a principle of honour, and the subordination of ranks, with the vigour of despotic authority, supply the place of virtue, by retraining irregularities and producing public order. But in free states, where the host of the people have the supreme power properly in their own hands, and must be ultimately resorted to on all great matters, if there be a general corruption of manners, there can be nothing but confusion. So true is this, that civil liberty cannot be long preserved without virtue. A monarchy may subsist for ages, and be better or worse under a good or bad prince; but a republic once equally poised, must either preserve its virtue or lose its liberty, and by some tumultuous revolution, either return to its first principles, or assume a more unhappy form.
[John Witherspoon, Sermons on Interesting Subjects, Sermon XXIII: Delivered at a public thanksgiving after peace, The Works of John Witherspoon, Volume 5, J. Ogle (Edinburgh: 1815) p. 266.]