This book is primarily a study of Man and ultimately embraces all the great qualities and problems of Man. As a study of Man it takes into consideration _all_ the characteristics which make Man what he is. If some readers do note the absence of certain expressions familiar to them, it does not mean that the author does not feel or think as many other people—he does—and very much so; but in this book an effort has been made to approach the problem of Man from a scientific-mathematical point of view, and therefore great pains have been taken _not_ to use words insufficiently defined, or words with many meanings. The author has done his utmost to use such words as convey only the meaning intended, and in the case of some words, such as “spiritual,” there has been superadded the word “so-called,” not because the author has any belief or disbelief in such phenomena; there is no need for _beliefs_ because some such phenomena exist, no matter what we may think of them or by what name we call them; but because the word “spiritual” is not scientifically defined, and every individual understands and uses this word in a _personal_ and private way. To be _im_personal the author has had to indicate this element by adding “so-called.” I repeat once again that this book is not a “materialistic” or a “spiritualistic” book—it is a study of “Man” and therefore does and _should_ include materialistic as well as spiritual phenomena because only the complex of these phenomena constitutes the complex of Man. The problem has not been approached from the point of view of any private doctrine or creed, but from a mathematical, an engineering, point of view, which is impersonal and passionless. It is obvious that to be able to speak about the great affairs of Man, his spiritual, moral, physical, economic, social or political status, it must first be ascertained what Man is—what is his real nature and what are the basic laws of his nature. If we succeed in finding the laws of human nature, all the rest will be a comparatively easy task—the ethical, social, economic and political status of Man should be in accord with the laws of his nature; then civilization will be a human civilization—a permanent and peaceful one—not before. It is useless to argue if electricity be “natural” or “_super_natural,” of “material” or of “spiritual” origin. As a matter of fact we do not ask these questions in studying electricity; we endeavor to find out the natural laws governing it and in handling live wires we do not argue or speculate about them—we use rubber gloves, etc. It will be the same with Man and the great affairs of Man—we have, first of all, to know what Man is.