[W]hy our nature was given a propensity toward desires of whose futility we are aware is an anthropological-teleological question. It seems that if we had to assure ourselves that we can in fact produce the object, before we could be persuaded [by the presentation] to apply our forces, then our forces would remain largely unused. For usually we do not come to know what forces we have in the first place except by trying them out.
Immanuel Kant, Critique of Judgment, translated by Werner S. Pluhar