Longtermism is an ethical position holding that positively influencing the long-term future is a key moral priority of our time, grounded in the claims that future people matter morally, that the future may contain vastly more people than the present, and that present actions can foreseeably shape their welfare. It motivates particular concern for reducing existential and catastrophic risks, safeguarding civilisational trajectory, and preserving option value for future generations. As a strand of effective altruism and applied ethics, longtermism informs governance debates on emerging technologies, biosecurity, and the safe development of advanced artificial intelligence.
Overview
- Longtermism developed within the effective altruism movement and global priorities research, notably articulated by philosophers such as Nick Bostrom, Toby Ord, and William MacAskill. Its central empirical premise is that the expected number of future people dwarfs the present population, so even small, durable improvements to humanity’s trajectory carry enormous moral weight.
- The view distinguishes weak longtermism (the future matters and deserves more attention than it currently receives) from strong longtermism (improving the far future is the most important consideration in many decisions).
- Practically, longtermism directs attention to reducing risks that could permanently curtail humanity’s potential, including engineered pandemics, nuclear conflict, and unaligned advanced AI Safety failures.
- Critics question the tractability of forecasting over long horizons, the risk of neglecting present suffering, and the philosophical assumptions underlying aggregation of future welfare.
Key aspects
Moral Standing of Future People
- The claim that people who do not yet exist have moral worth comparable to present people, motivating duties across time. Links to: Intergenerational Equity, Moral Philosophy.
Magnitude of the Future
- An empirical estimate that the potential future population vastly exceeds the present, amplifying the stakes of trajectory-shaping actions. Links to: Forecasting.
Existential Risk Reduction
- Prioritising the prevention of outcomes that would permanently destroy or drastically curtail humanity’s potential. Links to: Existential Risk, Catastrophic Risk.
Option Value and Trajectory Change
- Preserving the ability of future generations to make good choices, and steering long-run civilisational direction. Links to: Long-Term Governance.
Applications
- Funding and research prioritisation within Effective Altruism, directing resources toward neglected, high-leverage long-run causes.
- Shaping Technology Policy and governance frameworks for AI Alignment, biosecurity, and other dual-use technologies.
- Informing institutional design for Long-Term Governance, including future-generations commissioners and far-horizon impact assessment.
- Framing global catastrophic and existential risk analysis through structured Risk Assessment and Forecasting.