Act to Merit Eternity

Unamuno dismisses the demand that he resolve his contradictions before proceeding to ethics. He cannot resolve them, and neither can anyone else who has honestly faced the problem. The conflict between reason's denial and the heart's demand is not a preliminary obstacle to living well; it is the very condition within which living well must be attempted. The contradiction itself, sustained and accepted, is what drives genuine moral effort. A person who has resolved the tension — in either direction — no longer needs to strive.

Unamuno formulates his practical conclusion in language deliberately parallel to Kant's categorical imperative — but with an entirely different foundation. Instead of asking what a rational agent could universalise, Unamuno asks what would make a person genuinely irreplaceable. His imperative is to act in such a way that one's death would be a genuine loss to the universe — not merely the cessation of a social function but the destruction of something unique and irreplaceable. This is not an argument for personal survival; it is an argument for personal significance.

Unamuno ends not with a solution but with a charge: to shatter comfortable certainties wherever they are found, whether the certainty of the rationalist who has settled for a universe without God or the certainty of the orthodox believer who has settled for a God without mystery. The philosopher's task is to be a living disturbance — to keep alive, in the culture, the wound that comfortable thought would close. This is what Don Quixote does, and it is what Unamuno believed Spanish philosophy, at its best, had always done.

Chapter XI ('The Practical Problem') and the Conclusion together constitute Unamuno's answer to the question the whole book has prepared. The moral imperative to merit eternity anticipates themes developed by later existentialist ethics.