Longtermism

Longtermism is the view that the primary determinant of the value of our actions is their effects on the very long-term future — thousands, millions, or billions of years from now. The view was developed within effective altruism and is most closely associated with philosophers William MacAskill and Nick Bostrom. Its central claim is not merely that the future matters, but that it matters overwhelmingly: because the future could contain vastly more lives than the present, the expected value of actions that affect the long-term trajectory of civilization dominates the expected value of actions that affect only the present.

The argument is straightforward. Suppose humanity survives for another billion years at a population of ten billion. That is 10^19 future lives. Even a small probability of affecting whether those lives exist, or what their quality is, has astronomical expected value. A 0.0001% chance of preventing an existential catastrophe is, by this logic, more important than saving a million lives today. This is not a reductio. It is the view's central commitment.

Critics argue that longtermism is not merely demanding but structurally blind. It requires predicting the consequences of actions across timescales where prediction is impossible; it discounts the moral urgency of present suffering in favor of speculative future benefits; and it concentrates decision-making power in the hands of those who claim to know what the long-term future requires. The systems-theoretic critique is sharper: longtermism treats civilization as a trajectory that can be optimized, when the history of complex systems suggests that trajectories are shaped by feedback, contingency, and the irreducible plurality of values.

The political implications are significant. If the long-term future dominates moral decision-making, then the institutions and individuals who can influence that future — AI labs, governments, philanthropic organizations — acquire outsized moral authority. Longtermism is not merely a philosophical position. It is a framework for distributing moral and political power across time.