4. The following list of one hundred words will help you to develop fixity of thought and attention. You will notice that there is some connection between each pair of words: one suggests, includes, excludes, or is in contrast with the other. This is true of the entire list of words. You should be able, therefore, in a very short time, to repeat the whole list backwards and forwards quite rapidly. In order to do this, however, you will have to concentrate your mind on these words to the exclusion