According to our definition capital is the product of past industry used to further production.

Just when and how the first capital appeared it is impossible to say, difficult even to imagine. Primitive man working with his hands alone must have found it difficult to secure anything over and above bare subsistence; for even under the wildest condition we can hardly imagine that food, clothing, and shelter could ordinarily be procured in adequate amounts without labor. At some point in his development, however, we know that he began to create capital. Perhaps it was a bow and arrow he made, or a canoe, or a snare for small game, or a fish net. But where did he find the time for creating this capital? Perhaps a storm brought to the shore a surplus supply of fish, or an accident placed in his hands an extra deer. In either case he would find it possible to abstain a few days from the labor of getting food to sustain life. It is just as likely, however, that our primitive man, feeling instinctively the long-run gain to be had from the use of capital in production, consciously decreased his volume of consumption, even going hungry. Thus, by spending a part of each day in fashioning a crude tool or weapon, instead of spending his whole time in hunting or fishing, he was able eventually to create capital. We, his descendants, must do the same thing today if capital is to be increased or even conserved, and the first step to that end is to be able to curb desires and appetite.