This is that which I think great readers are apt to be mistaken in; those who have read of everything, are thought to understand everything too; but it is not always so. Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours. We are of the ruminating kind, and it is not enough to cram ourselves with a great load of collections ; unless we chew them over again, they will not give us strength and nourishment.
As quoted in "Hand Book : Caution and Counsels" in The Common School Journal Vol. 5, No. 24 (15 December 1843) by Horace Mann, p. 371