In general it is imperfect, in that the sustentation of multitudinous species depends on the wholesale destruction of others; so that, in the species serving as prey, the relations between conduct and consequence are so habitually broken that in very few individuals are they long maintained. It is true the destruction of the species serving as prey is the result of their natures; "but this violent ending of the immense majority implies that the species is one in which justice, as above conceived, is displayed in but small measure." Sub-human justice is also imperfect in detail, in that the relation between conduct and consequences is, in such an immense proportion of cases, broken by accidents,--such as scarcity of food, inclemencies of weather, invasions by parasites, attacks of enemies,--which fall indiscriminately on the superior and the inferior. As organization becomes higher, sub-human justice becomes more decided; as general superiority increases, there is less dependence on accident, and individual differences become more important. With the beginning of gregariousness, we find the new element of cooeperation, passive or active, which is an advantage to the species. This involves so much restraint of conflicting acts as will leave a balance of advantage; else survival of the fittest will exterminate the variety in which association begins. The experience of the evils of not maintaining such limits to action results in an inherited tendency to maintain them. The general consciousness of the need for maintaining them results in punishment of their disregard. Self-subordination among solitary animals is found only in parenthood; among gregarious animals there is a further subjection of the individual to his kind, and where an occasional sacrifice of life furthers the preservation of species, sub-human justice may rightly have this second limitation.