Every individual should find a vocation furnishing that one of the three kinds of work for which he has the greatest ability. Then he should go into the particular branch of that vocation which is best adapted to his personality, training, education, environment and experience. To be a success you must produce something out of the ordinary for the world. And you will produce nothing unusual save what your particular organism was built to produce. To know what this is, classify the kind of activities you take to naturally. You can be a star in some line that calls for those activities. You will never succeed in any calling which demands the opposite kinds of activities or reactions. Read in English (unabridged).