These variations complicate economical phenomena, and often render them very difficult of observation and solution.

I know no remedy for this; it is not in our power to change the nature of things." 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.