Other things being equal, a person whose power of retention is good has a great advantage over his fellows who have poor ability to remember. Suppose we consider the learning of language. The pupil who can look up the meaning of a word just once and remember it has an advantage over the person who has to look up the meaning of the word several times before it is retained. So in any branch of study, the person who can acquire the facts in less time than another person, has the extra time for learning something else or for going over the same material and organizing it better. The scientist who remembers all the significant facts that he reads, and sees their bearing on his problems, has a great advantage over the person who does not remember so well. Of course, there are certain dangers in having a good memory, just as there is danger in being brilliant generally. The quick learner is in danger of forming slovenly habits. A person who learns quickly is likely to form the habit of waiting till the last minute to study his lesson and then getting a superficial idea of it. The slow learner must form good habits of study to get on at all. Teachers and parents should prevent the bright children from forming bad habits of study. The person who learns quickly and retains well should be taught to be thorough and to use the advantage that comes from repetition. The quick learner should not be satisfied with one attack on his lesson, but should study the lesson more than once, for even the brilliant learner cannot afford to neglect the advantages that come from repetition. A person with poor memory and only mediocre ability generally can make up very much by hard work and by work that takes advantage of all the laws of economical learning. But he can never compete successfully with the person who works as hard as he does and who has good powers of learning and retention. The author has found that in a large class of a hundred or more, there is usually a person who has good memory along with good mental ability generally, and is also a hard worker. Such a person always does the best work in the class. A person with poor memory and poor mental powers generally cannot hope to compete with a person of good memory, good mental powers generally, if that person is also a good worker.