No League of Nations, or of individuals, can avail, without a change of heart. Reformers of all classes must recognize that it is useless to preach peace by itself, or socialism by itself, or anti-vivisection by itself, or vegetarianism by itself, or kindness to animals by itself. The cause of each and all of the evils that afflict the world is the same the general lack of humanity, the lack of the knowledge that all sentient life is akin, and that he who injures a fellow-being is in fact doing injury to himself. The prospects of a happier society are wrapped up in this despised and neglected truth, the very statement of which, at the present time, must (I well know) appear ridiculous to the accepted instructors of the people. — Seventy Years Among Savages
Salt summed up his humanitarian principles in The Creed of Kinship:
1. That our present so called "Civilisation" is only a "manner of speaking," and is in fact quite a rude state as compared with what may already be foreseen.
2. That the basis of any real morality must be the sense of Kinship between all living beings.
3. That there can be no abiding national welfare until the extremes of Wealth and Poverty are established.
4. That Warfare will not be discontinued until we have ceased to honour soldiering as heroic.
5. That the Rights of Animals have henceforth to be considered; and that such practices as cruel sports, vivisection, and flesh eating are not compatible with civilised life.
6. That Free Thought is essential to progress, and that the religion of the future will be a belief in a Creed of Kinship, a charter of human and sub-human relationship.