Is it necessary to prove that, if nature had destined man to a [p117] solitary life, the prosperity of one would have been incompatible with that of another, and the more numerous men had been, the less chance would they have had of attaining prosperity? At all events, we see clearly in what way numbers might have been injurious, and we do not see how they could have been beneficial. And then, I would ask, under what form could the principle of sympathy have manifested itself? How, or on what occasion, could it have been called forth? Could we have even comprehended it? But men exchange, and Exchange, as we have seen, implies the separation of employments. It gives birth to professions and trades. Each man sets himself to overcome a certain class of obstacles, for the benefit of the Community. Each makes it his business to render a certain description of ‹services›. Now, a complete analysis of value demonstrates that each service ‹has value› in the first instance in proportion to its intrinsic utility, and afterwards in proportion to the wealth of those to whom it is furnished—that is to say, in proportion as the community to whom the service is rendered has a greater demand for it, and is in a better situation to pay for it. Experience shows us that the artizan, the physician, the lawyer, the merchant, the carrier, the professor, the ‹savant›, derive greater returns from their services in Paris, in London, or at New York, than in the Landes of Gascony, or the mountains of Wales, or the prairies of the Far West. And does not this confirm the truth, ‹that each man is more likely to prosper in proportion to the general prosperity of the community in which he lives›? Of all the harmonies which have come under my observation, this is beyond doubt the most important, the finest, the most decisive, the most suggestive. It sums up and includes all the others. This is why I can give only a very incomplete demonstration of it in this place. The whole scope and spirit of this work will establish it; and I shall deem it a fortunate thing if its probability at least is made so apparent as to induce the reader to convince himself of its truth by farther inquiry and reflection.