The sanctity or dangerousness of the chief is probably due, first, to his being really dangerous; but, secondly, to the biological advantage to a tribe of respecting him, which leads to a selection of those tribes amongst whom respect for the chief arises. As biological adaptation is never more than a moving, oscillating equilibrium, this feeling sometimes becomes excessive, even to the point of insanity. Everything the chief touches becomes taboo; only a few sacred servants can approach him; he may be thus reduced to helplessness. It is one of Nature’s checks upon tyranny. Such is the force of taboo, that a Maori tribesman, being hungry, seeing some food by the wayside, and eating it, on learning that it was the remains of the meal of a sacred chief, immediately fell ill, and died. The offence was fatal—as soon as it was known. The dangerousness of women has been referred to their weakness; association with them must be weakening, and is therefore forbidden when exertion is needed.[135] Prof. Westermarck traces it to a “horror of blood”;[136] very probably; but other things may co-operate towards it. The life of women separates them from men, and brings them into a freemasonry and community of interests, to which men are not admitted; differentiates their mentality, until the result is mysterious and therefore magical: the sexual orgasm, being more like pain than anything that is not pain, at once attractive and revulsive, acquires the same character. Homicides and mourners, again, are liable to be taboo, either because there clings to them the mysterious quality and taint of death (a magical motive), or because they are followed by the ghosts of the departed.