210 OF THE ADVANCEMENT OF LEARNING. [XXI.8 
8. The opinion of Aristotle seemeth to me a negligent 
opinion, that of those things which consist by nature, 
nothing can be changed by custom; using for example, 
that if a stone be thrown ten thousand times up, it will 
not learn to ascend; and that by often seeing or hearing, 
we do not learn to see or hear the better. For though 
this principle be true in things wherein nature is per- 
emptory (the reason whereof we cannot now stand to 
discuss), yet it is otherwise in things wherein nature 
admitteth a latitude. For he mought see that a strait 
glove will come more easily on with use; and that a 
wand will by use bend otherwise than it grew; and that — 
by. use of the voice we speak louder and stronger; and 
that by use of enduring heat or cold, we endure it the 
better, and the like: which latter sort have a nearer re- 
semblance unto that subject of manners he handleth, 
than those instances which he allegeth. But allowing 
his conclusion, that virtues and vices consist in habit, he 
ought so much the more to have taught the manner of 
superinducing that habit: for there be many precepts 
of the wise ordering the exercises of the mind, as there 
is of ordering the exercises of the body; whereof we will 
recite a few. 
g. The first shall be, that we beware we take not at 
the first, either too high a strain, or too weak: for if 
too high, in a diffident nature you discourage, in a con- 
fident nature you breed an opinion of facility, and so a 
sloth; and in all natures you breed a further expectation 
than can hold out, and so an insatisfaction in the end: if 
too weak, of the other side, you may not look to perform 
and overcome any great task. 
ro. Another precept is, to practise all things chiefly at 
two several times, the one when the mind is best dis- 
