"Nunquam tutelae suae fiunt." ["They are ever in wardship."--Seneca, Ep., 33.] I was privately carried at Pisa to see a very honest man, but so great an Aristotelian, that his most usual thesis was: "That the touchstone and square of all solid imagination, and of all truth, was an absolute conformity to Aristotle's doctrine; and that all besides was nothing but inanity and chimera; for that he had seen all, and said all." A position, that for having been a little too injuriously and broadly interpreted, brought him once and long kept him in great danger of the Inquisition at Rome. Let him make him examine and thoroughly sift everything he reads, and lodge nothing in his fancy upon simple authority and upon trust. Aristotle's principles will then be no more principles to him, than those of Epicurus and the Stoics: let this diversity of opinions be propounded to, and laid before him; he will himself choose, if he be able; if not, he will remain in doubt. "Che non men the saver, dubbiar m' aggrata." ["I love to doubt, as well as to know."--Dante, Inferno, xi. 93] for, if he embrace the opinions of Xenophon and Plato, by his own reason, they will no more be theirs, but become his own. Who follows another, follows nothing, finds nothing, nay, is inquisitive after nothing. "Non sumus sub rege; sibi quisque se vindicet." ["We are under no king; let each vindicate himself." --Seneca, Ep.,33] Let him, at least, know that he knows. It will be necessary that he imbibe their knowledge, not that he be corrupted with their precepts; and no matter if he forget where he had his learning, provided he know how to apply it to his own use. Truth and reason are common to every one, and are no more his who spake them first, than his who speaks them after: 'tis no more according to Plato, than according to me, since both he and I equally see and understand them. Bees cull their several sweets from this flower and that blossom, here and there where they find them, but themselves afterwards make the honey, which is all and purely their own, and no more thyme and marjoram: so the several fragments he borrows from others, he will transform and shuffle together to compile a work that shall be absolutely his own; that is to say, his judgment: his instruction, labour and study, tend to nothing else but to form that. He is not obliged to discover whence he got the materials that have assisted him, but only to produce what he has himself done with them. Men that live upon pillage and borrowing, expose their purchases and buildings to every one's view: but do not proclaim how they came by the money. We do not see the fees and perquisites of a gentleman of the long robe; but we see the alliances wherewith he fortifies himself and his family, and the titles and honours he has obtained for him and his. No man divulges his revenue; or, at least, which way it comes in but every