Rationality as Fluent Thinking
The demand for rationality is, at bottom, a demand for the removal of intellectual friction. When we find that a chaos of facts can be expressed by a single formula, we feel a release of mental tension — the pleasure of seeing many things become one. This relief is the positive feeling of rationality. It explains why simplicity, elegance, and unity are prized in theories: they are indices of the frictionless thinking that rationality makes possible.
Two Demands in Tension
But the demand for simplicity is only one side of rationality. There is also the demand that our principles apply to the concrete reality we actually inhabit — that they make contact with the peculiarities of experience and not merely float above them. These two demands — for simplicity and for coverage — are permanently in tension. Every philosophical system is a compromise between them, and no system wholly satisfies both.
Well, of two conceptions equally fit to satisfy the logical demand, that one which awakens the active impulses, or satisfies other aesthetic demands better than the other, will be accounted the more rational conception, and will deservedly prevail.
Action as the Touchstone of Reason
The deepest criterion of rationality is its relation to action. A philosophy that satisfies the intellect but leaves us passive and disengaged from the demands of life has missed something essential. The sentiment of rationality, fully realised, is not just intellectual ease but the ease of a person who knows what to do — whose understanding and will are aligned. This is why James insists that active impulse is a legitimate criterion of philosophical worth: thinking exists in the service of living.
"The Sentiment of Rationality" first appeared in Mind in 1879 and was substantially revised for The Will to Believe (1897). It is one of James's earliest and most architecturally important philosophical essays.
Related Concepts
