The secret of philosophy, said Leibnitz, is to treat familiar things as unfamiliar. By the secret of “philosophy” Leibnitz meant the secret of what we call science. Let us apply this wholesome maxim in our present study; let us, in so far as we can, regard the familiar terms—wealth, capital and money—as unfamiliar; let us deal with them afresh; let us examine openmindedly the facts—the phenomena—to which the terms relate and ascertain scientifically the significance the terms must have in a genuine science of human economy. Examine “the facts” I say—examine “the phenomena”—for bending facts to theories is a vital danger, while bending theories to facts is essential to science and the peaceful progress of society. Human beings have always had some sense of values—some perception or cognition of values. In order to express or measure values, it was necessary to introduce units of measure, or units of exchange. People began to measure values by means of agricultural and other products, such as cattle, for example. The Latin word for cattle was _pecus_, and the word _pecunia_, which came to signify money, accounts for the meaning of our familiar word pecuniary. The earliest units for measuring became unsuited to the increasing needs of growing trade, “business,” or traffic. Finally a unit called money was adopted in which the base was the value of some weight of gold. Thus we see that money came to mean simply the accepted unit for measuring, representing and expressing values of and in wealth. But what is wealth? I have said that the old conceptions of wealth, capital and money—the conceptions that are still current throughout the world—belong to the period of humanity’s childhood—they are childish conceptions. I have said that they must be replaced by scientific conceptions—by conceptions fit for humanity’s manhood. The change that must be made in our conceptions of the great terms is tremendous. It is necessary to analyse the current conceptions of wealth, capital, and money—the childish conceptions of them—in order to reveal their falseness, stupidity and folly. To do this we must enter the field of Political Economy—a field beset with peculiar difficulties and dangers. All the Furies of private interests are involved. One gains the impression that there is little or no real desire to gain a true conception—a scientific conception—of wealth. Everybody seems to prefer an emotional definition—a definition that suits his personal love of wealth or his hatred of it. Many definitions of wealth, capital and money are to be found in modern books of political economy—definitions and books belonging to humanity’s childhood. For the purpose of this writing they all of them look alike—they sufficiently agree—they are all of them childish. Mill, for example, tells us that wealth consists of “useful or agreeable things which possess exchangeable value.” Of capital one of the simplest definitions is this: