“William James thus presented pragmatism as a ‘method for settling metaphysical disputes that might otherwise be interminable.’ (1907: 28) Unless some ‘practical difference’ would follow from one or the other side’s being correct, the dispute is idle.
[T]he tangible fact at the root of all our thought-distinctions, however subtle, is that there is no one of them so fine as to consist in anything but a possible difference of practice. To attain perfect clearness in our thoughts of an object, then, we need only consider what conceivable effects of a practical kind the object may involve—what sensations we are to expect from it, and what reactions we must prepare. (1907: 29)”
1907. Pragmatism: A New Name for some Old Ways of Thinking, Cambridge, MA: Harvard University Press, 1975.