The Three-Part Case for Longtermism
- Difficulty
- Advanced
- Time to result
- ~ongoing to results
- Steps
- 5
- Confidence
- —
Longtermism evaluates present choices by their effects on the full future of civilization. Its mechanism has three parts. First, future people have moral worth even though they live at a different time, just as geographic distance does not erase moral worth. Second, humanity's potential future is immense: civilization could persist for hundreds of thousands, millions, or far more years, making future lives vastly more numerous than present lives. Third, actions taken during an unusually powerful technological period may alter that entire trajectory. Extinction could eliminate the future altogether, while ideological or institutional lock-in could shape its quality indefinitely. The framework therefore directs attention toward interventions that protect civilization's lifespan, preserve its quality, and retain flexibility for future moral progress.
Origin
Extracted from Deep Dive with Ali Abdaal
How to run it
- 1
Zoom out in time
Place the present within humanity's long past and potentially much longer future rather than focusing only on the current election or generation.
Pro tip Compare humanity's 300,000-year past with the possible lifespan of a species or civilization.
- 2
Recognize future moral worth
Ask whether a harm or benefit would matter less merely because its recipient lives hundreds or thousands of years from now.
Pro tip Use a fixed future harm, such as a genocide, to separate moral worth from uncertainty.
Watch out Uncertainty about whether an event occurs is different from discounting the people affected.
- 3
Estimate the potential scale
Consider how many lives and how much welfare could exist if civilization survives for a very long time.
Pro tip Use conservative and ambitious ranges rather than relying on a single forecast.
- 4
Identify trajectory-changing pathways
Look for events that could cause extinction, permanently curtail civilization, or lock in harmful values and institutions.
Pro tip Separate effects on civilization's lifespan from effects on its quality.
Watch out Do not restrict long-term impact to literal human extinction.
- 5
Prioritize robust safeguards
Support research, policy, technology, and institutions that reduce major risks while retaining value across multiple plausible futures.
Pro tip Favor broadly protective measures when the precise future threat is uncertain.
Watch out Speculative importance should still be balanced against tractability and evidence.
In the wild
MacAskill asks whether preventing a genocide should matter less if it occurs in one hundred, one thousand, or two thousand years. Holding the event and certainty constant isolates the moral question: temporal distance alone does not appear to erase the victims' worth.
→ Future people remain morally relevant even when additional uncertainty affects practical decisions.
An engineered pathogen could end humanity's future, while an AI-enabled totalitarian system could allow civilization to continue under a harmful ideology that persists indefinitely. One pathway affects the length of the future; the other affects its quality.
→ Long-term strategy must address both survival and the values or institutions that govern surviving civilization.
Common mistakes
Equating uncertainty with irrelevance
Impacts farther in the future may be harder to predict, but that does not make the people affected morally worthless.
Focusing only on extinction
A future can survive while becoming permanently authoritarian, impoverished, or otherwise much worse.
Assuming the future is beyond influence
Technological risks and institutional choices made today may shape civilization for an exceptionally long time.
From the transcript
“future people matter”
“the third idea is that we really can make a difference not just to the present day but actually to the entire course of future…”
“if the human race goes extinct we're not coming back from that”
From the episode
Moral Philosopher Will MacAskill on What We Owe The Future