As seen above, Plato was the first great economic thinker of Greece.68 Plato, however, was primarily interested in neither economics nor politics, but in moral idealism. He is pre-eminent, even among the Socratics, for this. All his economic thought is a direct outgrowth of it, and is shot through with its influence.
Yet, despite this fact, he exhibits considerable insight into some of the basal principles of economics,69 and his entire Republic is founded upon an essentially economic theory of society. He traces its origin to mutual need,70 and makes little of the innate social impulse, so prominent in Aristotle’s analysis.71
He is the predecessor of Aristotle, however, in opposing the social contract doctrine of the Sophists with its interpretation of law as mere convention, by a natural theory of social origins. To his thought, the very foundations of society are established in eternal justice. They are not the result of mere convention, nor altogether the work of inspired lawgivers, but a complex product of natural and artificial elements.72
VALUE
Strictly speaking, Plato’s contribution to a theory of economic value and a definition of wealth is practically nil. In his discussion of just price, he merely hints at the fact of exchange value. He implies that, since goods exchange according to definite proportions, they should have a common quality capable of measurement, and that just price corresponds to this.73 He offers no suggestion as to the nature of this quality, except that, in stating that “the artisan knows what the value of his product is,” he