This book was written by a medical doctor in 1923, a time when with almost no access to massive communication, people could concentrate better on their selves.

There is not a magical formula to get mental supremacy, however with a series of very simple exercises mental efficiency could be improved. The methods presented require no@previous training nor specialized knowledge and even children can easily apply them.

Thinking process involves several stages:

1. Perception 2. Memory 3. Association of memories 4. Judgment 5. Will

1. All we have in our mind came through the senses, therefore we have to learn how to fine our senses.

2. Perceptions are only useful if we can remember them, so we have to sharp our memory.

3. Isolated memories are of few value, their value increase when we are able to associate them.

4. A storm of associated memories are of little use except if we learn how to classify them.

5. In order to do anything with the mind (or with the body either, for that matter) one must choose, must wish to do that thing, and this choice, this decision to do something is called will.

The stages of the thinking process are interconnected and exercising one function we are exercising all the others. The book presents several kinds of exercises for each stage, exercises can be easily modified and new ones can be created according to the reader's preferences. No results however are guaranteed without a minimal of constant dedication.

Improving of the mental faculties, by the other hand, depends on several subjective factors. Even if we don't reach mental supremacy, this book can help us to improve our way of thinking, and any attempt to improve ourselves is worthwhile.