“Obest plerumque iis, qui discere volunt,
               auctoritas eorum, qui docent.”

     ["The authority of those who teach, is very often an impediment to
     those who desire to learn.”—­Cicero, De Natura Deor., i. 5.]

It is good to make him, like a young horse, trot before him, that he may judge of his going, and how much he is to abate of his own speed, to accommodate himself to the vigour and capacity of the other.  For want of which due proportion we spoil all; which also to know how to adjust, and to keep within an exact and due measure, is one of the hardest things I know, and ’tis the effect of a high and well-tempered soul, to know how to condescend to such puerile motions and to govern and direct them.  I walk firmer and more secure up hill than down.

Such as, according to our common way of teaching, undertake, with one and the same lesson, and the same measure of direction, to instruct several boys of differing and unequal capacities, are infinitely mistaken; and ’tis no wonder, if in a whole multitude of scholars, there are not found above two or three who bring away any good account of their time and discipline.  Let the master not only examine him about the grammatical construction of the bare words of his lesson, but about the sense and let him judge of the profit he has made, not by the testimony of his memory, but by that of his life.  Let him make him put what he has learned into a hundred several forms, and accommodate it to so many several subjects, to see if he yet rightly comprehends it, and has made it his own, taking instruction of his progress by the pedagogic institutions of Plato.  ’Tis a sign of crudity and indigestion to disgorge what we eat in the same condition it was swallowed; the stomach has not performed its office unless it have altered the form and condition of what was committed to it to concoct.  Our minds work only upon trust, when bound and compelled to follow the appetite of another’s fancy, enslaved and captivated under the authority of another’s instruction; we have been so subjected to the trammel, that we have no free, nor natural pace of our own; our own vigour and liberty are extinct and gone: 

“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.