I have also tested the matter out in other ways. I have experimented with a group of men and women, by reading a passage of about a page in length, repeating the reading till the subject could reproduce all the facts. It was found that the person who acquired all the facts from the fewest readings remembered more of the facts later. It must be said that there is less difference between the subjects later than at first.

In the laboratory of Columbia University a similar experiment was performed, but in a somewhat different way. Students were required to commit to memory German vocabularies and were later tested for their retention of the words learned. It was found that those who learned the most words in a given time, also retained the largest percentage of what had been learned. It should not be surprising that this is the case. The quick learner is the one who makes the best use of all the factors of retention, the factors mentioned in the preceding paragraph—good attention, association, organization, etc.

Another experiment performed in the author’s laboratory bears out the above conclusions. A group of students were required to commit to memory at one sitting a long list of nonsense syllables. The number of repetitions necessary to enable each student to reproduce them was noted. One day later, the students attempted to reproduce the syllables. Of course they could not, and they were then required to say them over again till they could just repeat them from memory. The number of repetitions was noted. The number of repetitions was much less than on the first day. On the third day, the process was repeated. The number of repetitions was fewer still. This relearning was kept up each day till each person could repeat the syllables from memory without any study. It was found that the person who learned the syllables in the fewest repetitions the first time, relearned them in the fewest repetitions on succeeding days. All the experiments bearing on the subject point to the same conclusion; namely, that the quick learner, if other things are equal, retains at least as well as the slow learner, and usually retains better.

Transfer of Memory Training. We have said above that there are many kinds or aspects of memory. It has also been said that we can improve memory by practice. Now, the question arises, if we improve one aspect of memory, does this improve all aspects? This is an important question; moreover, it is one to be settled by experiment and not by argument.

The most extensive and thorough experiment was performed by an English psychologist, Sleight. The experiment was essentially as follows: He took a large number of pupils and tested the efficiency of the various aspects of their memory. He then took half of them and trained one aspect of their memory until there was considerable improvement. The other section had no memory training meanwhile. After the training, both groups again had all aspects of their memory tested. Both groups showed improvement in all aspects because the first tests gave them some practice, but the group that had been receiving the training was no better in those aspects not trained than was the group receiving no training at all. Aspects of memory much like the one trained showed some improvement, but other aspects did not.

The conclusion is that memory training is specific, that it affects only the kind of memory trained, and related memories. This is in harmony with what we learned about habit. When we receive training, it affects only the parts of us trained and other closely related parts.

Learning by Wholes. We do not often have to commit to memory verbatim, but when we do, it is important that we should know the most economical way. Experiments have clearly demonstrated that the most economical way is to read the entire selection through from beginning to end and continue to read it through in this way till the matter is learned by heart.

In long selections, the saving by this method is considerable. A pupil is not likely to believe this because if he spends a few minutes learning in this manner, he finds that he cannot repeat a single line, while if he had concentrated on one line, he could have repeated at least that much. This is true; but although he cannot repeat a single line by the whole procedure, he has learned nevertheless. It would be a good thing to demonstrate this fact to a class; then the pupils would be satisfied to use the most economical procedure. The plan holds good whether the matter be prose or poetry.

But experiments have been carried on only with verbatim learning. The best procedure for learning the facts so that one can give them in one’s own words has not yet been experimentally determined.

Cramming. An important practical question is whether it pays to go over a great amount of material in a very short time, as students often do before examinations. From all that has been said above, one could infer the solution to this problem. Learning and memorizing are to some extent a growth, and consequently involve time.