What We Owe the Future

MacAskill's case rests on a deceptively simple chain of premises: people who don't exist yet still matter morally, there could be an almost unimaginable number of them if civilization survives and spreads, and the choices made in the next few decades could shape their lives for better or catastrophically worse. From this he builds "longtermism," the view that positively influencing the deep future is one of the great undertakings available to people alive today, on par with abolishing slavery or preventing a world war. He treats humanity as still very early in its story — potentially thousands or millions of years from its end — which means present-day decisions about technology, values, and survival carry outsized leverage over an enormous stretch of future experience.

The argument matters because it reframes urgency: climate change, pandemics engineered or natural, and the unpredictable trajectory of advanced artificial intelligence aren't just this century's problems, they're potential permanent forks in civilization's road, some of which could "lock in" bad values or end the human story altogether. MacAskill's contribution is less a doom-laden warning than a call to treat existential risk reduction and moral progress as practical, tractable work rather than abstract philosophizing.

Who should read it

This suits readers curious about effective altruism, existential risk, or the philosophical weight of future generations, especially those who want rigorous argument rather than dystopian speculation. It rewards patience with abstract thought experiments about population ethics and probability, and may frustrate readers looking for concrete policy prescriptions rather than a framework for thinking.

About the author

William MacAskill is a Scottish moral philosopher and associate professor at the University of Oxford, and a co-founder of the effective altruism movement and the organization Giving What We Can.