From this example let us take warning, that facts be not to us nothing more than round stones. Let us be careful never to let our minds rest content with the mere accumulation of facts, but ever strive to build them up into something more useful and ennobling. Let us use them as bricks—mere logs of burnt clay in themselves, but fit to build glorious monuments of the sublime power of human invention. Let us remember that Ideas are the only things of real permanent value in this world; and that, though we may store our brain with Facts till our heads burst, unless those facts are to us only generators of Ideas, we have not, and cannot acquire a Cogitative mind; we may have Knowledge, but we have not Wisdom. A wise man hath wisely said, that “the wise man is”—not he who knoweth _things_, but—“he who knoweth the _interpretation_ of a thing” [_Eccles._ viii. 21]; and for this purpose only it is that, “Wise men lay up knowledge” [_Prov._ x. 14], for “Wisdom finds out knowledge of witty inventions” [_Prov._ viii. 12]. In order to effectually discipline the mind to attentive study, and to save it from the strong temptation which is offered to desultory reading, it is advisable for the adult and partially educated student to form an hypothesis and read up to it. To reverse, in fact, the Baconian principles of philosophy, and to study from hypothesis to facts, and not from facts to hypothesis. This is, it is true, opposed to modern philosophical principles, but properly modified and carefully guarded against self-conceit and dogmatism, it is almost the only proper and effective mode of study. It is the ancient or Aristotelian mode; and though, when refuted by Bacon, as a mode of “discovering the sciences,” it had become shamefully abused and degenerate, it has produced more great original thinkers than the modern. Observe, that we recommend it only as a mode of _study_, _i. e._, of disciplining and exercising the mind, for beyond the purpose of _training_ it should not be pursued. It is too dangerous to be prosecuted far, for the mind which has long formed and nursed up a favourite hypothesis is unwilling to abandon it, and is too apt to force all facts into accordance with it, instead of modifying or abandoning it as new facts arise.[26]