Elsewhere Say says, and repeats, that value being based on utility, and utility depending entirely on our needs, whims, customs, &c., value is as variable as opinion. Now, political economy being the science of values, of their production, distribution, exchange, and consumption,--if exchangeable value cannot be absolutely determined, how is political economy possible? How can it be a science? How can two economists look each other in the face without laughing? How dare they insult metaphysicians and psychologists? What! that fool of a Descartes imagined that philosophy needed an immovable base--an _aliquid inconcussum_--on which the edifice of science might be built, and he was simple enough to search for it! And the Hermes of economy, Trismegistus Say, devoting half a volume to the amplification of that solemn text, _political economy is a science_, has the courage to affirm immediately afterwards that this science cannot determine its object,--which is equivalent to saying that it is without a principle or foundation! He does not know, then, the illustrious Say, the nature of a science; or rather, he knows nothing of the subject which he discusses. Say's example has borne its fruits. Political economy, as it exists at present, resembles ontology: discussing effects and causes, it knows nothing, explains nothing, decides nothing. The ideas honored with the name of economic laws are nothing more than a few trifling generalities, to which the economists thought to give an appearance of depth by clothing them in high-sounding words. As for the attempts that have been made by the economists to solve social problems, all that can be said of them is, that, if a glimmer of sense occasionally appears in their lucubrations, they immediately fall back into absurdity. For twenty-five years political economy, like a heavy fog, has weighed upon France, checking the efforts of the mind, and setting limits to liberty. Has every creation of industry a venal, absolute, unchangeable, and consequently legitimate and true value?--Yes. Can every product of man be exchanged for some other product of man?--Yes, again. How many nails is a pair of shoes worth? If we can solve this appalling problem, we shall have the key of the social system for which humanity has been searching for six thousand years. In the presence of this problem, the economist recoils confused; the peasant who can neither read nor write replies without hesitation: "As many as can be made in the same time, and with the same expense."