Sir William Hamilton, 9th Baronet

The instructor... does not profess to teach philosophy, but to philosophise.

[I]nstruction is only instruction as it enables us to teach ourselves.

[U]niversities... have gradually allowed to fall into disuse the powerful means which they possess of rousing the pupil to exertion, and have been too often content to act as mere oral instruments of information...

On this ground I would rest one of the pre-eminent utilities of mental philosophy. That it comprehends all the sublimest objects of our theoretical and moral interest; that every (natural) conclusion concerning God, the soul, the present …

Scotus... declares that a man’s knowledge is measured by the amount of his mental activity...

"The intellect," says Aquinas, "commences in operation, and in operation it ends..."

"The intellect," says Aristotle... "is perfected, not by knowledge but by activity..." and... "The arts and sciences are powers, but every power exists only for the sake of action; the end of philosophy... is not knowledge, but the energy …

Plato defines man "the hunter of truth," "for science is a chase, and in a chase the pursuit is always of greater value than the game."

[I]n the very term Philosophy... the man who first declared that he was not a... possessor, but a... seeker of truth, at once enounced the true end of human speculation, and embodied it in a significant name.

The past does not interest, the present does not satisfy, the future alone is the object which engages us.

"In life," as the great Pascal observes, "we always believe that we are seeking repose, while, in reality, all that we ever seek is agitation."

[T]he sciences always studied with keenest interest are those in a state of progress and uncertainty: absolute certainty and absolute completion would be the paralysis of any study; and the last worst calamity that could befall man... …

"Sordet cognita veritas" is a shrewd aphorism of Seneca. A truth, once known, falls into comparative insignificance.

The question—Is Truth, or is the Mental Exercise in the pursuit of truth, the superior end?—this is perhaps the most curious theoretical, and certainly the most important practical, problem in the whole compass of philosophy.

The one condition under which all powers, and consequently the intellectual faculties, are developed, is exercise.

Truth like a torch, the more 'tis shook, it shines.

The primary principle of education is the determination of the pupil to self-activity — the doing nothing for him which he is able to do for himself.

Be sober, and to doubt prepense, These are the sinews of good sense.