While these different kinds or aspects of memory may have some relation
to one another, they are to some extent independent. One may have a good
rote memory and a poor logical memory, or a poor rote memory and a good
logical memory. That is to say, one may be very poor at remembering the
exact words of a book, but be good at remembering the meaning, the
ideas, of the book. One may be good at organizing meaningful material
but poor at remembering mere words. On the other hand, these conditions
may be reversed; one may remember the words but never get the meaning.
It is of course possible that much of this difference is due to habit
and experience, but some of the difference is beyond doubt due to
original differences in the nervous system and brain. These differences
should be determined in the case of all children. It is quite a common
thing to find a feeble-minded person with a good rote memory, but such a
person never has a good logical memory. One can have a good rote memory
without understanding, one cannot have a good logical memory without
understanding.

Let us now ask the question, why can one remember better words that are
connected by logical relations than words that have no such connection?
If we read to a person a list of twenty nonsense words, the person can
remember only two or three; but if a list of twenty words connected in a
sentence were read to a person, in most cases, all of them would be
reproduced. The reason is that the words in the latter case are not new.
We already know the words. They are already a part of our experience. We
have had days, perhaps years, of experience with them. All that is now
new about them is perhaps a slightly new relation.

Moreover, the twenty words may contain but one, or at most only a few,
ideas, and in this case it is the ideas that we remember. The ideas hold
the words together. If the twenty words contain a great number of ideas,
then we cannot remember all of them from one reading. If I say, "I have
a little boy who loves his father and mother very much, and this boy
wishes to go to the river to catch some fish," one can easily remember
all these words after one reading. But if I say, "The stomach in all the
Salmonidae is syphonal and at the pylorus are fifteen to two hundred
comparatively large pyloric coeca"; although this sentence is shorter,
one finds it more difficult to remember, and the main reason is that the
words are not so familiar.

=Memory and T