In short, within the tribe the rule of "each for all" is supreme, so long as the separate family has not yet broken up the tribal unity. But that rule is not extended to the neighbouring clans, or tribes, even when they are federated for mutual protection. Each tribe, or clan, is a separate unity. Just as among mammals and birds, the territory is roughly allotted among separate tribes, and, except in times of war, the boundaries are respected. On entering the territory of his neighbours one must show that he has no bad intentions. The louder one heralds his coming, the more confidence he wins; and if he enters a house, he must deposit his hatchet at the entrance. But no tribe is bound to share its food with the others: it may do so or it may not. Therefore the life of the savage is divided into two sets of actions, and appears under two different ethical aspects: the relations within the tribe, and the relations with the outsiders; and (like our international law) the "inter-tribal" law widely differs from the common law. Therefore, when it comes to a war the most revolting cruelties may be considered as so many claims upon the admiration of the tribe. This double conception of morality passes through the whole evolution of mankind, and maintains itself until now. We Europeans have realized some progress--not immense, at any rate--in eradicating that double conception of ethics; but it also must be said that while we have in some measure extended our ideas of solidarity--in theory, at least--over the nation, and partly over other nations as well, we have lessened the bonds of solidarity within our own nations, and even within our own families.