Opens in a new tab
16 min 09 sec
Available in:English

What We Owe the Future

Makes the case that people who will live centuries from now deserve real weight in today's decisions, and shows how values, new technology, existential risks and your own money and career choices can shape their lives.

Table of Content

Most of us judge our choices by their effect on the people around us, this year. In What We Owe the Future, Oxford philosopher William MacAskill argues that the circle should be far wider: a child cut by broken glass a century from now is hurt just as badly as one cut tomorrow. Future people count, even though they do not exist yet.

MacAskill calls this outlook longtermism, and its claim is simple and demanding. People not yet born matter as much as we do, there may be vast numbers of them, and what we do in this century can decide whether their lives go well or badly. The argument runs from slavery and artificial intelligence to asteroids, engineered viruses and coal, then comes down to the scale of one life. Along the way it gives you a way to judge which causes deserve your money, your vote and your working hours, and a reason to believe one person’s choices still shape history.

A broken bottle on a forest trail turns into a test of how far your concern really reaches. The answer changes once you consider how many people might still be coming, and how much we already shape their lives.

Slavery was profitable, ancient and defended by the powerful, yet it ended. MacAskill argues the reason was far less certain than we like to think, and that should worry anyone who cares about what the world believes.

Software can be copied endlessly and almost never dies. MacAskill explains why that makes one kind of machine a threat to moral change itself, and what kind of world could guard against it.

Scientists warning about asteroids were laughed at for years, until a comet hit another planet. What followed shows how fast a danger can fall, and which far larger dangers MacAskill thinks deserve that treatment now.

If almost everyone died tomorrow, the libraries and machines would still be standing. MacAskill points to a different missing ingredient that could keep survivors from ever climbing back, and it is being used up today.

Most people pick a cause because it touched someone they love, and a career by drifting into it. MacAskill offers a sharper method for both, and it starts with three plain rules about acting under uncertainty.

MacAskill went vegetarian at 18 to do good, then ran the numbers on it. The comparison he found is striking, and his most surprising recommendation for protecting the future has nothing to do with diet or charity.

MacAskill asks for one change of view with large effects: stop treating the date of a harm as morally relevant. Once you do, the people who come after us become the largest group touched by anything we do, and the only one without a voice. They have no way to vote, lobby, stand for office, publish articles or take part in protests. What we decide for them, we decide alone.

From their side, this century carries unusual weight. Values could harden through AGI, a virus could be designed in a lab, fuel a broken world would need could be burned, and a shrinking population could stall invention. Spaceguard shows the other possibility: serious attention cut a danger a hundredfold.

The practical advice is modest in size. Before you give, compare what your money does with another use, the way a $3,000 donation outweighed a lifetime of vegetarian meals. Treat your next career move as a test you will review in two years. Raise the problems that matter with people close to you, because MacAskill notes that every movement in history was built from individual efforts added together. The child on that forest path has not been born yet, and the broken glass is still yours to pick up.

About this book

What is this book about?

Most moral thinking stops at the people we can see: family, neighbors, voters, customers. William MacAskill, an Oxford philosopher who co-founded the Centre for Effective Altruism, asks what happens when we take seriously the people who will come after us. If humanity lasts for hundreds of millions of years, he estimates that each person alive now could be matched by a million people yet to be born, and none of those people can vote or protest. MacAskill calls this view longtermism. He uses the end of slavery to show how fragile moral progress is, warns that artificial general intelligence could freeze one set of values in place for good, and weighs threats such as engineered pandemics and the loss of the fossil fuels a collapsed civilization would need to rebuild. The NASA asteroid program Spaceguard shows that serious attention can cut such dangers sharply. The book then turns practical. Readers get rules of thumb for choosing causes, a way to treat a career as an experiment, and comparisons showing why a well-placed donation can outweigh years of personal sacrifice.

Book Information

Rating:

Genre:

Philosophy, Technology & the Future

Topics:

Artificial Intelligence, Ethics, Risk Management

Publisher:

Hachette

Language:

English

Narrator:

Meredith

First published:

January 1, 2022

Pages:

368

Length:

16 min 09 sec

Get the book:

Amazon

Who it's for

  • Professionals wanting lasting impact

    Professionals who want their career, donations and votes to count for more than the next quarter.

  • Career changers weighing causes

    Career switchers deciding what problem deserves their next decade of work.

  • Curious about existential risk

    Readers curious about AI, pandemics and existential risk who want a moral framework for thinking about them.

Listen to Preview

About the Author

William MacAskill

William MacAskill is a Scottish philosopher, born in Glasgow in 1987, who has served as an associate professor of philosophy at the University of Oxford. He co-founded Giving What We Can, which asks people to pledge at least 10 percent of their income to effective charities, as well as the Centre for Effective Altruism and 80,000 Hours, which advises people on careers that make a difference. His earlier book is Doing Good Better.

Ratings & Reviews

Ratings at a glance

4.3

Overall score based on 253 ratings.

What people think

Listeners find the work to be intellectually stimulating and meticulously researched, with one listener mentioning that it is packed with intriguing case studies. They view it as a straightforward yet absorbing listen that is both brief and skillfully composed. Listeners categorize it as exceptionally vital, and one listener emphasizes its creative perspectives on human extinction. The text receives varied reactions concerning its overall academic rigor and narrative arrangement.

Top reviews

Pear

Picked this up on a whim after seeing the cover, and I’m genuinely glad I did. MacAskill uses this brilliant analogy of humanity being like molten glass that is currently malleable but destined to cool and set into a rigid shape. That image haunted me throughout the chapters on moral lock-in. It’s a sobering thought that the values we choose to prioritize today—or the ones we ignore—could become the permanent foundation for trillions of people yet to come. The book is meticulously documented but stays incredibly readable, even when diving into the dense world of population ethics. I particularly enjoyed the section on how the abolition of slavery wasn't an economic inevitability but a contingent moral choice. It makes you realize that our current 'normal' is just as fragile. This is the kind of big-picture thinking we desperately need right now.

Show more
Wei

Finally got around to this long-termist manifesto and it’s a total perspective shifter. Truth is, I haven't been able to stop thinking about the 'contingency' of our values since I finished it. We like to think that society just naturally gets better over time, but MacAskill proves that progress is often the result of lucky breaks and small groups of dedicated people. It’s empowering and terrifying all at once. The writing is concise and avoids the usual academic jargon that kills these types of philosophy books. I loved the bits about keeping coal in the ground not just for the climate, but to ensure future civilizations have the resources to rebuild if we collapse. It’s a wild, sweeping, and ultimately hopeful book. If you want to feel a sense of agency in a chaotic world, read this. It is a massive achievement.

Show more
Palm

Wow. This is arguably one of the most important books I’ve read this decade. MacAskill presents a compelling, sometimes frightening, look at existential risk that refuses to settle for easy doomerism. The analogy of humanity as a teenager—full of potential but lacking impulse control—is pitch-perfect. We have so much to lose. While some sections on moral value contingency were a bit dense, the overall message of responsibility is impossible to ignore. Truly transformative stuff for anyone worried about our legacy. It changed how I view my career and my daily impact. A must-read.

Show more
Laor

After hearing MacAskill on a few podcasts, I expected a dry lecture on statistics, but this was surprisingly soulful. The way he frames humanity as an imprudent teenager—full of potential but prone to self-destruction—is a masterstroke of communication. He argues that we are at a unique crossroads where our decisions have outsized influence on the long-term future. The chapter on technological stagnation was particularly eye-opening for me. We assume progress is an inevitable escalator, but he shows how easily we could stall out or backslide. My only gripe is that he occasionally brushes off the 'partiality' argument too quickly. Look, I care about the future, but I’m always going to care about my own family more than a trillion hypothetical people in the year 30,000. Still, it's a compelling and extraordinarily important read for our era.

Show more
Ahmed

What We Owe the Future is a dense but surprisingly readable dive into how our current choices might echo for millennia. MacAskill is at his best when he’s describing the risks of 'value lock-in,' particularly with the rise of AI. The idea that a single, flawed ideology could be enforced forever is the stuff of nightmares. I found his defense of population growth to be the most controversial but also the most thought-provoking part of the book. Even if you don't agree that 'more happy people is always better,' he forces you to reckon with the logic of your own intuitions. The book is full of interesting case studies—like the Glyptodons or the specific history of sugar taxes—that keep the abstract philosophy grounded. It's not a perfect blueprint, but it's a vital conversation starter for anyone who cares about our species' legacy.

Show more
Pensri

As someone who generally finds Effective Altruism a bit cold, I was surprised by how much heart MacAskill managed to inject into these pages. He handles the heavy lifting of population ethics with a lightness that avoids the usual academic sludge. The chapter on technological stagnation really stuck with me. We often assume progress is an infinite, upward-climbing escalator, but he argues quite persuasively that it might be more like a ladder we could easily fall off. This book is essentially a call to action to become 'moral entrepreneurs.' While I don't buy into every statistical model he presents—especially the ones regarding animal neuron counts—the overarching message is hard to argue with. We are the ancestors of a vast future, and we are currently acting like terrible ones. This book is a much-needed nudge to grow up and start taking our long-term survival seriously.

Show more
Pui

Is this book overly optimistic or just deeply naive? MacAskill’s central idea—that we should plan for trillions of humans who don't exist yet—is intellectually stimulating but feels profoundly out of touch with the struggle of the present. Personally, I found the suggestion to simply 'pick a progressive career' to be a bit of a slap in the face for people without Oxford degrees. To be fair, the research is top-notch and the case studies are genuinely fascinating. The historical deep-dives into social movements were the highlight for me. However, I can't shake the feeling that this brand of 'kinder capitalism' is just moving the deck chairs on the Titanic. It’s a well-written book with some innovative ideas about human extinction, but it smells a lot like Ivory Tower navel-gazing. Useful for a debate, but maybe not for real-world change.

Show more
Kung

The central premise here is undeniably fascinating, yet the execution feels like a series of missed connections. MacAskill wants us to treat the future as a moral priority. That makes sense. But the math feels hollow when applied to the messy, unpredictable reality of human behavior. Frankly, the section on 'expected-value theory' felt like trying to use a ruler to measure the taste of an apple. It’s too clinical for the subject matter. He talks about nuclear holocaust as a statistical probability, which somehow strips away the actual human tragedy of the lives already here. I appreciated the deep dive into the history of the British abolitionist movement, which was a great example of 'moral entrepreneurship.' However, the book as a whole feels like a collection of very high-quality blog posts that don't quite cohere into a singular, practical guide.

Show more
Anawin

Gotta say, the first half of this book is electric, but it loses a lot of steam toward the end. The opening chapters on the sheer scale of the potential future are mind-blowing. It really puts our current political squabbles into perspective. However, when MacAskill starts getting into the weeds of 'population ethics' and the 'Repugnant Conclusion,' it starts feeling like philosophical masturbation. He spends so much time on hypothetical trillion-person civilizations that he loses sight of the world we’re actually living in. I found myself agreeing with the concept of longtermism but rolling my eyes at the proposed implementations. Donating a percentage of your salary to funky charities feels like a very 'Oxford' solution to global catastrophe. It’s an interesting thought experiment, but as a practical guide for the average person, it falls short. Interesting to look at, but the substance is a bit dry.

Show more
Eleni

Not what I expected from an Oxford philosopher. While the book starts with a noble premise, it quickly devolves into some really questionable logic regarding the value of sentient life. I was particularly frustrated by his attempt to measure suffering through neuron counts. To suggest that a human's pain matters more than a farm animal's simply because of 'receptor quantity' is a logic that many psychotherapists and activists would find absurd. It feels like he’s trying to 'solve' morality with a calculator. The discussion on identity was equally puzzling, making big claims about how small decisions completely change who we are. Not gonna lie, it felt like the author was laundering some pretty cold, utilitarian ideas through a friendly narrative. There are better books on the future that don't treat living beings like units of currency. It’s polished, but fundamentally flawed in its moral core.

Show more
Show all reviews

Questions about this book

William MacAskill argues for longtermism: future people count as much as people alive today, there could be enormous numbers of them, and our choices now can shape whether their lives go well. He estimates that if humanity lasts until Earth can no longer be lived on, every person alive today could be matched by a million people yet to come, which makes protecting the long-term future among the most important things we can do.

Value lock-in is any event that lets one system of values persist for an extremely long time. MacAskill points to the end of slavery, helped along by a small group of Quaker activists, to show that moral progress was never certain. He fears artificial general intelligence could freeze one set of values permanently, so he argues for a morally exploratory world and experiments such as charter cities.

MacAskill focuses on human-made threats. Engineered pandemics could combine the lethality of Ebola with the contagiousness of measles, and various estimates put the chance of an extinction-level one this century between 0.6 and 3 percent. He also warns that using up fossil fuels could seriously hamper recovery after a collapse, and that technological stagnation could leave us with dangerous tools but no defenses.

MacAskill suggests choosing actions you are confident are good, keeping your options open and continuing to learn. Prioritize causes by global impact rather than closeness to home. Compare options by measured effect, as a $3,000 donation to the Clean Air Task Force outweighs a lifetime of vegetarianism in carbon terms. Vote, talk about important issues with friends, and treat your career as a hypothesis you test and revise.

It suits people who want their careers, giving and political choices to make a lasting difference, especially those choosing or changing careers. It also serves readers who follow debates about artificial intelligence, pandemics and climate and want a single moral framework that connects them, written by a philosopher who co-founded Giving What We Can and 80,000 Hours.

AUDIO SUMMARY AVAILABLE

Listen to What We Owe the Future in 15 minutes

Get the key ideas from What We Owe the Future by William MacAskill, plus 5,000+ more nonfiction titles.

  • 5,000+ titles
  • Listen as much as you want
  • 7-day free trial
  • Cancel anytime

What We Owe the Future

Preview · Full summary 16 min 09 sec
Home

Discover

Open app

Log in