The Life of Reason: The Phases of Human Progress

What makes a life rational, if no law is handed down from above? Santayana’s answer is that reason is simply a creature’s impulses arranged so that they can be satisfied together.

Reason here is not a faculty set over the passions but the work of the passions themselves, each learning to make room for the others. Ideals grow out of nature and have no other home; an ideal is what an impulse would be if it were fully satisfied. That places the book against every philosophy that finds the warrant for morality in a world beyond this one. The family, the state, the church and the arts are then judged by one test: how well each serves a life in which many goods can be had at once.

• reason
• rationality
• human nature
• human flourishing
• happiness
• moral psychology
• ethics
• naturalism
• ideals
• emotion
• nature

How does a mind build a stable world out of the flux of sensation, and why does progress depend on keeping hold of it? The famous sentence about forgetting the past belongs to this argument.

Reason in Common Sense traces how perception, memory and language turn a stream of feeling into a world of objects and other minds. Progress, on this account, is not change but retentiveness: a creature that cannot keep what experience has taught it must learn the same lessons again, like an infant who never grows up. The sentence about those who cannot remember the past, much quoted and commonly misunderstood, belongs here, as a claim about what any mind needs in order to improve rather than a warning about history lessons.

• memory
• experience
• perception
• consciousness
• representation
• epistemology
• empiricism
• language

If religions are myths, why do they matter so much, and what makes one better than another? Reason in Religion measures each faith by how much of life it brings into order.

Religion, in Santayana’s account, pursues the same end as reason by imaginative means: its myths express, in the form of stories about gods, what a people has learned about living well. It becomes a rival of reason only when its myths are taken for literal fact and set up against knowledge. A religion is to be judged, then, not by whether its stories happened but by how much of human life it rationalises, how many impulses it disciplines and harmonises, and how much it leaves out.

• religion
• mythology
• myth
• imagination
• idealism
• metaphysics
• ideals

Is fine art a separate realm with its own laws, or one part of the general work of making the world fit to live in? Reason in Art takes the second view and asks what art adds to happiness.

Art, broadly understood, is any activity that shapes matter toward a human purpose, and the fine arts are the part of that activity whose products are good to contemplate. Santayana refuses them any exemption: a work of art is justified by what it contributes to a rational life, not by an autonomy of the aesthetic. His warmth goes to art, poetry above all, that gives the ideals of a life a form in which they can be seen and loved, and his coolness to art that asks to be valued apart from any life at all.

• aesthetics
• poetry
• imagination
• representation
• emotion
• happiness

What can knowledge really claim? Reason in Science divides it between physics, which traces how matter moves, and dialectic, which unfolds what ideas mean, and denies either the other’s office.

Physics studies existence and finds mechanism throughout; dialectic, from logic to ethics, studies the implications of ideas and finds necessity there. Trouble begins when one is mistaken for the other, when a dialectical system claims to describe the world, or when mechanism is expected to supply values. Santayana grants science its whole province, and grants it no more. Knowledge of nature tells a creature how to reach its ends; only its own ideals tell it which ends are worth reaching.

• science
• philosophy of science
• dialectic
• naturalism
• metaphysics
• rationality