ters, such as following the will of God, are unascertainable and vague. Others again, like survival, are quite indeterminate in their consequences, and leave us in the lurch where we most need their help: a philosopher of the Sioux Nation, for example, will be certain to use the survival-criterion in a very different way from ourselves. The best, on the whole, of these marks and measures of goodness seems to be the capacity to bring happiness. But in order not to break down fatally, this test must be taken to cover innumerable acts and impulses that never aim at happiness; so that, after all, in seeking for a universal principle we inevitably are carried onward to the most universal principle,—that the essence of good is simply to satisfy demand. The demand may be for anything under the sun. There is really no more ground for supposing that all our demands can be accounted for by one universal underlying kind of motive than there is ground for supposing that all physical phenomena are cases of a single law. The elementary forces in ethics are probably as plural as those of physics are. The various ideals have no common character apart from the fact that they are ideals. No single abstract principle can be so used as to yield to the philosopher anything like a scientifically accurate and genuinely useful casuistic scale.
A look at another peculiarity of the ethical universe, as we find it, will still further show us the philosopher's perplexities. As a purely theoretic problem, namely, the casuistic question would hardly ever come up at all. If the ethical philosopher were only asking after the best imaginable system of goods he would indeed have an easy task; for all demands as
