It has been well said that "Man might be defined to be an animal that makes exchanges."[6] There are other animals, indeed, such as bees and ants amongst insects, and beavers amongst quadrupeds, which to a certain extent are social; that is, they concur together in the execution of a common work for a common good: but as to their individual possessions, each labours to obtain what it desires from sources accessible to all, or plunders the stores of others. Not one insect or quadruped, however wonderful may be its approaches to rationality, has the least idea of making a formal exchange with another. The modes by which the inferior animals communicate their thoughts are probably not sufficiently determinate to allow of any such agreement. The very foundation of that agreement is a complicated principle, which man alone can understand. It is the Security of individual Property. Immediately that this principle is established, labour begins to work profitably, for it works with exchange. If the principle of appropriation were not acted upon at all, there could be no exchange, and consequently no production. The scanty bounty of nature might be scrambled for by a few miserable individuals--and the strongest would obtain the best share; but this insecurity would necessarily destroy all accumulation. Each would of course live from hand to mouth, when the means of living were constantly exposed to the violence of the more powerful. This is the state of the lowest savages, and as it is an extreme state it is a rare one,--no security, no exchange, no capital, no labour, no production. Let us apply the principle to an individual case.