The practical grounds for justice, listed on the previous page, deal only with human capabilities; consequently, the concept properly applies only to human action and its consequences. Moreover, justice (like any other virtue) can only be practiced by human beings. For both of these reasons, it makes no sense to pass moral judgment on nature (apart from human action) or to regard nature as "just" or "unjust": the concept does not apply in this context. To lament the "injustice" of natural circumstances beyond human control serves no cognitive or practical function. Rand called such circumstances "metaphysically given," because they are determined, not by human volition, but by the natures of nonhuman entities. To complain against the supposed inequity of nature—as opposed to injustices arising from human actions—represents merely an irrational and self-destructive revolt against reality, and not any concern about true justice.

For example, suppose that Crusoe, unexpectedly marooned on an island with only a man-eating tiger for company, cries out in rage: "Life isn't fair!" Certainly we can sympathize with his plight, and his anger is a natural psychological defense mechanism for dealing with sudden, overwhelming emotional pain and fear. Crusoe's survival, however, will require mental clarity—which means that he will need to come to terms rapidly not only with these underlying feelings but also with his adverse existential circumstances.