Our study of the relation between mind and body at this time has had a deeper, broader and more vital purpose. It is the foundation stone of an educational structure in which we shall show you how the mind may be brought by scientific measures to a certainty and effectiveness of operation far greater than is now common or ordinarily thought possible. [Sidenote: Your Reservoir of Latent Power] Remember the two fundamental propositions set forth in this book. I. _All human achievement comes about through some form of bodily activity._ II. _All bodily activity is caused, controlled and directed by the mind._ The truth of these propositions must now be obvious to you. You must realize that the mind is the one instrument by which it is possible to achieve anything in life. Your next step must be to learn how to use it. _In succeeding volumes, we shall sound the depths of the reservoir of latent mental power. We shall find the means of tapping its resources. And so we shall come to give you the master key to achievement and teach you how to use it with confidence and with the positive assurance of success._ End of Project Gutenberg's Psychology and Achievement, by Warren Hilton