The intellect," says Aquinas, "commences in operation, and in operation it ends... - Sir William Hamilton, 9th Baronet

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

The discovery of the art of Printing unbarred afresh the gates of Heaven, and let in that flood of light, of knowledge, and of wisdom, which enabled men to emancipate themselves again from the slavery of superstition—to take their proper place in the ranks of created beings—and in ennobling themselves, in gradually exalting their understandings and amending their hearts, to pay at length the worthiest homage to the goodness of their common Parent, and prove themselves to be—as the Almighty himself originally formed them—inferior only to the Angels.

[T]he paramount end of liberal study is the development of the student’s mind, and... knowledge is principally useful as a mean of determining the faculties to that exercise, through which this development is accomplished... the main duty of a Professor to consist not simply in communicating information, but in doing this in such a manner... that the information he conveys may be the occasion of awakening his pupils to a vigorous and varied exertion of their faculties.