Yet the existence of evil is the chief reason for the existence of religion, at least of such religions as promise salvation, and the explanation of evil is the chief problem of all religions and philosophies, and the problem which they all alike are conspicuously unsuccessful in solving. I can assign no reason for rejecting as untenable the idea that the ultimate reality may be a duality—a good and an evil spirit—or even a plurality[73], but still it is unthinkable for me and I believe for most minds. If there are two ultimate beings, either they must be complementary and necessary one to the other, in which case it seems to me more correct to describe them as two aspects of one being, or if they are quite separate, my mind postulates (but I do not know why) a third being who is the cause of them both. The problem of evil is not quite the same for Indian and European pantheists. The European pantheist holds that since God is all things or in all things, evil is only something viewed out of due perspective: that the world would be seen to be perfect, if it could be seen as a whole, or that evil will be eliminated in the course of development. But he cannot explain why the partial view of the world which human beings are obliged to take shows the existence of obvious evil. The Hindus think that it is possible and better for the soul to leave the vain show of the world and find peace in union with God. They are therefore not concerned to prove that the world is good, although they cannot explain why God allows it to exist. The Upanishads contain some myths and parables about the introduction of evil but they do not say that a naturally good world was spoilt[74]. They rather imply that increasing complexity involves the increase of evil as well as of good. This is also the ground thought of the Aggañña Sutta, the Buddhist Genesis (Dig. Nik. XXVII.).