useless to mankind, merely because it has not been reasoned upon!
The trifling observation, that a straight stick appears bent in water,
was made many hundred years before the reason of that appearance was
discovered! The invention of the telescope might have been made by any
person who could have pursued this slight observation through all its
consequences.

Having now defined, or rather described, what we mean by _a good
memory_, we may consider how the memory should be cultivated. In
children, as well as in men, the strength of that habit, or perhaps of
that power of the mind which associates ideas together, varies
considerably. It is probable, that this difference may depend
sometimes upon organization. A child who is born with any defect in
his eyes, cannot possibly have the same pleasure in objects of sight,
which those enjoy who have strong eyes: ideas associated with these
external objects, are, therefore, not associated with pleasure, and,
consequently, they are not recollected with any sensations of
pleasure. An ingenious writer[51] supposes, that all the difference of
capacity amongst men ultimately depends on their original power of
feeling pleasure or pain, and their consequent different habits of
attention.

When there is any defect in a child's organization, we must have
recourse to physics, and not to metaphysics; but even among children,
who are apparently in the full possession of all their senses, we see
very different degrees of vivacity: those who have most vivacity,
seldom take delight in repeating their ideas; they are more pleased
with novelty than prone to habit. Those children who are deficient in
vivacity, are much disposed to the easy indolent pleasure of
repetition; it costs them less exertion to say or do the same thing
over again, than to attempt any thing new; they are uniformly good
subjects to habit, because novelty has no charms to seduce their
attention.

The education of the memory in these two classes of children, ought
not to be the same. Those who are disposed to repetition, should not
be indulged in it, because it will increase their indolence; they
should be excited by praise, by example, by sympathy, and by all the
strongest motives that we can employ. Their interest in every thing
around them must by all means be increased: when they show eagerness
about any thing, no matter what it is, we may then exercise their
memory upon that subject with some hopes of success. It is o