obtain them all.

Undigested learning is as useless and oppressive as undigested food; and
as in the dyspeptic patient the appetite for food often grows with the
inability to digest it, so in the unthinking patient an overweening
desire to know often accompanies the inability to know to any purpose.
Thought is to the brain what gastric juice is to the stomach,--a
solvent to reduce whatever is received to a condition in which all that
is wholesome and nutritive may be appropriated, and that alone. To learn
merely for the sake of learning, is like eating merely for the taste
of the food. The mind will wax fat and unwieldy, like the body of the
gormand. The stomach is to the frame what memory is to the mind; and it
is as unwise to cultivate the memory at the expense of the mind, as it
would be to enlarge the capacity of the stomach by eating more food than
the wants of the frame require, or food of a quality that it could not
appropriate. To learn in order to become wise makes the mind active and
powerful, like the body of one who is temperate and judicious in meat
and drink. Learning is healthfully digested by the mind when it reflects
upon what is learned, classifies and arranges facts and circumstances,
considers the relations of one to another, and places what is taken into
the mind at different times in relation to the same subjects under their
appropriate heads, so that the various stores are not heterogeneously
piled up, but laid away in order, and may be referred to with ease when
wanted. If a person's daily employments are such as demand a constant
exercise of the thoughts, all the leisure should not be devoted to
reading, but a part reserved for reflecting upon and arranging in the
mind what is read. The manner of reading is much more important than
the quantity. To hurry through many books, retaining only a confused
knowledge of their contents, is but a poor exercise of the brain; it is
far better to read with care a few well-selected volumes.