Here, then, you have the plain alternative, and the full mystery of the difference between pluralism and monism, as clearly as I can set it forth on this occasion. It packs up into a nutshell:--Is the manyness in oneness that indubitably characterizes the world we inhabit, a property only of the absolute whole of things, so that you must postulate that one-enormous-whole indivisibly as the _prius_ of there being any many at all--in other words, start with the rationalistic block-universe, entire, unmitigated, and complete?--or can the finite elements have their own aboriginal forms of manyness in oneness, and where they have no immediate oneness still be continued into one another by intermediary terms--each one of these terms being one with its next neighbors, and yet the total 'oneness' never getting absolutely complete?
The alternative is definite. It seems to me, moreover, that the two horns of it make pragmatically different ethical appeals--at least they _may_ do so, to certain individuals. But if you consider the pluralistic horn to be intrinsically irrational, self-contradictory, and absurd, I can now say no more in its defence. Having done what I could in my earlier lectures to break the edge of the intellectualistic _reductiones ad absurdum_, I must leave the issue in your hands. Whatever I may say, each of you will be sure to take pluralism or leave it, just as your own sense of rationality moves and inclines. The only thing I emphatically insist upon is that it is a fully co-ordinate hypothesis with monism. This world _may_, in the last resort, be a block-universe; but on the other hand it _may_ be a universe only strung-along, not rounded in and closed. Reality _may_ exist distributively just as it sensibly seems to, after all. On that possibility I do insist.
One's general vision of the probable usually decides such alternatives. They illustrate what I once wrote of as the 'will to believe.' In some of my lectures at Harvard I have spoken of what I call the 'faith-ladder,' as something quite different from the _sorites_ of the logic-books, yet seeming to have an analogous form. I think you will quickly recognize in yourselves, as I describe it, the mental process to which I give this name.