We ought to be able to show some practical difference

From Selected Writings by William James, page 2.

I tell this trivial anecdote because it is a peculiarly simple example of what I wish now to speak of as THE PRAGMATIC METHOD. The pragmatic method is primarily a method of settling metaphysical disputes that otherwise might be interminable. Is the world one or many?--fated or free?--material or spiritual?--here are notions either of which may or may not hold good of the world; and disputes over such notions are unending. The pragmatic method in such cases is to try to interpret each notion by tracing its respective practical consequences. What difference would it practically make to anyone if this notion rather than that notion were true? If no practical difference whatever can be traced, then the alternatives mean practically the same thing, and all dispute is idle. Whenever a dispute is serious, we ought to be able to show some practical difference that must follow from one side or the other's being right.