Every intuition, then, becomes concrete as a judgment, equivalent to a conclusion. But what seems obscure and even mysterious in it is the fact that, from among many possible solutions, it finds at the first shot the proper one. In my opinion this difficulty arises largely from a partial comprehension of the problem. By "intuition" people mean only cases in which the divination is correct; they forget the other, far more numerous, cases that are failures. The act by which one reaches a conclusion is a special case of it. What constitutes the originality of the operation is not its accuracy, but its _rapidity_--the latter is the essential character, the former accessory. Further, it must be acknowledged that the gift of seeing correctly is an inborn quality, vouchsafed to one, denied to another:--people are born with it, just as they are born right-or left-handed: experience does not give it--only permits it to be put to use. As for knowing why the intuitive act now succeeds and at another time fails, that is a question that comes down to the natural distinction between accurate and erroneous minds, which we do not need to examine here. Without dwelling longer on this initial stage, let us return to the commercial imagination, and follow it in its development. II The human race passed through a pre-commercial age. The Australians, Fuegians, and their class seem to have had no idea whatever of exchange. This primitive period, which was long, corresponds to the age of the horde or large clan. Commercial invention, arising like the other forms from needs,--simple and indispensable at first, artificial and superfluous later,--could not arise in that dim period when the groups had almost their sole relations with one another as war. Nothing called it to arise. But at a higher stage the rudimentary form of commerce, exchange in kind or truck, appeared early and almost everywhere. Then this long, cumbersome, inconvenient method gave place to a more ingenious invention--the employment of "standard values," beings or material objects serving as a common measure for all the rest:--their choice varied with the time, place, and people--e.g., certain shells, salt, cocoa-seeds, cloth, straw-matting, cattle, slaves, etc.; but this innovation held all the remainder in the germ, for it was the first attempt at substitution. But during the earliest period of commercial evolution the chief effort at invention consisted of finding increasingly more simple methods in the mechanism of exchange. Thus, there succeeded to these disparate values, the precious metals, in the form of powder and ingots, subject to theft and the inconveniences of weighing. Then, money of fixed denomination, struck under the authority of a chief or of a social group. Finally, gold and silver are replaced by the letter of credit, the bank check, and the numerous forms of fiduciary money.[132]