Planning for the future can feel insurmountable in the face of looming present-day challenges, but in What We Owe the Future (Basic Books, Aug.), philosopher and author William MacAskill advocates for longtermism, a view that suggests that looking to the health of our future civilization and shared planet is not only imperative for generations of people to come but also can positively impact the present.

Can you discuss your background?

I’m a philosophy professor at the University of Oxford. When I was in graduate school, I became concerned by the many pressing problems in the world and wanted to know how I could use my time and money to best make progress on them. This is what led me to start the effective altruism movement—a philosophy and community committed to using evidence and reason to figure out how to benefit others as much as possible and taking action on that basis. I started giving away over 10% of my annual income to effective charities focused on global health, and I founded Giving What We Can, a nonprofit that encourages others to donate as well. After that, I cofounded 80,000 Hours, a nonprofit that conducts research and offers guidance to students on which careers have the largest positive social impact. I also wrote Doing Good Better, an introductory text to effective altruism.

Over time, I became convinced that one of the best ways to promote the common good is by improving the lives of future generations, who get no say in our present-day decision-making. So when the pandemic started in 2020, I dropped everything and spent two years dedicated to research and writing for What We Owe the Future.

How do you define "longtermism"?

Longtermism is the view that positively influencing the long-term future is a key moral priority of our time. The case for longtermism is based on simple ideas: that, impartially considered, future people present generation; that there may be a huge number of future people; that life, for them, could be extraordinarily good or inordinately bad; and that we really can make a difference to the world they inhabit. A long-term perspective is crucial because we’re so early in history: if humanity survives to even a fraction of its potential life span, then, strange as it may seem, we are the ancients; we live at the very beginning of history, in the most distant past.

Does this mean sacrificing the needs of the present?

No. As I’ve learned more about longtermism, I’ve realized that we can positively impact the long-term future while making the world a better place today. Consider pandemic prevention. Longtermist researchers had been sounding the alarm bell about pandemics since 2014—years before Covid-19, which has now killed many millions of people. We need to learn that lesson and prevent the next pandemic, which could be even worse.

"MacAskill delivers a sweeping analysis of contemporary dangers that masterfully probes the intersections of technology, science, and politics, while offering fascinating glimpses into humanity’s possible futures. This urgent call to action will inspire and unnerve in equal measure." – Publishers Weekly

You write about your initial hesitance to embrace longtermism because you recognized that many needs and challenges weren’t being met in the present. What made you ultimately change your perspective?

A few things. First, there is remarkable overlap between the best ways we can promote the common good now and for future generations. In addition to preparing for the next pandemic, these include fighting extreme climate change, reducing the risk of a great power war, improving the values that guide society, and responsibly governing the development of advanced artificial intelligence (AI).

Second, as I learned more about the potentially history-shaping events that could occur in the near future, I took more seriously the idea that we might soon be approaching a critical juncture in the human story. Until recently, it would have been nearly impossible for humanity to cause its own collapse or extinction. Now, we could kill ourselves off with biological weapons or wage a nuclear war that causes civilization to collapse and never recover. And the rapid advances toward general AI is perhaps an even bigger deal: along with other technologies, I think it could have the potential to bring about the end of moral progress, or even lock in a single totalitarian regime.

Finally, I came to see concern for future generations as continuous with other moral movements that have inspired me, such as women’s rights and civil rights. Future generations are utterly disenfranchised in the world today: they can’t vote, or lobby, or bargain with us. So it’s not surprising that issues that impact them are neglected by the world today. We need a movement of morally motivated people to stand up for their interests.

It strikes me that longtermism is more than a moral philosophy; it’s a viewpoint with real-world applications. What are actionable steps readers can take in their own lives to embrace longtermism?

The most important ethical decision you make is the career that you pursue. A typical career lasts for 80,000 hours: about 40 hours of work a week, 50 weeks a year, for 40 years. Most people don’t spend nearly as much time as they should thinking about what to do with their career. You might think it’s reasonable to spend six minutes discussing where to go for a two-hour dinner. If you applied the same logic to thinking about your 80,000-hour-long career, you should be willing to do 4,000 hours of research. That’s a couple of years of full-time work.

"Warning: This book may radically upgrade your ethics and expand your compassion." – AJ Jacobs, editor at large, Esquire Magazine

In What We Owe the Future, I offer a three-step guide to choosing an impactful career:

  1. Learn: Find low-cost ways to learn about and try out promising longer-term paths, until you feel ready to bet on one for a few years.
  2. Build options: Take a bet on a longer-term path that could go really well (seeking upsides), usually by building the career capital that will most accelerate you in it. But in case it doesn’t work out, have a backup plan to cap your downsides.
  3. Do good: Use the career capital you’ve built to support the most effective solutions to the most pressing problems.

"MacAskill makes a moral case for the future that is urgent, clear, and utterly convincing." – Larissa MacFarquhar, staff writer, The New Yorker

Another crucial ingredient is personal fit. Some people are happiest locked away for months on end researching abstruse topics in economics or computer science, while others excel at managing a team or communicating ideas in a simple and engaging way. The people I know who are having the greatest positive impact with their career usually love what they do and stay motivated even when the going gets rough.

Beyond career choice, personal donations are an excellent way to improve the long-run future. There are outstanding opportunities to prevent the next pandemic, safely govern advanced artificial intelligence, and promote better values, which I discuss in the book.

The internet and social media have connected us in ways that—in the not-too-distant past—we couldn’t have envisioned. And yet, we are starkly divided along social and political lines. Does longtermism have the potential to unite us?

In one study on the idea of "utopia," there was surprisingly little difference between the left and the right on visions of what a good future looks like. So I (optimistically!) believe that there is a lot of potential here: people of all demographics, nationalities, and political views could come to see ourselves as engaging in a shared project—safeguarding civilization for our descendants, guarding against global control by any single ideology, and ensuring we continue to make moral progress into the future.

Climate change is becoming less of an abstract threat and more of a present danger with tangible consequences. Do you see an opportunity for galvanization as we witness raging wildfires and rising sea levels in real time?

Yes, absolutely! Thanks in part to youth activism already, several key players have made ambitious climate pledges, most notably China, which plans to reach zero emissions by 2060.

However, it’s crucial that we do not get complacent. One thing I try to do in What We Owe the Future is draw attention to some of the worst-case climate scenarios, which often go under-studied even though they would be the worst from a longtermist perspective. If progress on climate change stalled and we ultimately burn through all recoverable fossil fuels, there would most likely be around seven degrees of warming relative to the preindustrial period. This would be utterly catastrophic.

As you write in the book, uncertainty about the future can sometimes become an excuse for inaction. How do we plan for the distant future when we don’t know what lies ahead?

In What We Owe the Future, I use an analogy: that trying to improve the long-term future is like undertaking an expedition into uncharted terrain. I suggest we can employ three rules of thumb. First, we can take actions that we can be comparatively confident are good. If we are exploring uncharted territory, we know that tinder and matches, a sharp knife, and first aid supplies will serve us well in a wide range of environments. Even if we have little idea what our expedition will involve, these things will be helpful.

Second, we can try to increase the number of options open to us. On an expedition, we would want to avoid getting stuck down a ravine we can’t get out of, and if we weren’t certain about the location of our destination, we would want to choose routes that leave open a larger number of possible paths. Third, we can try to learn more. Our expedition group could climb a hill in order to get a better view of the terrain or scout out different routes ahead. These three lessons—take robustly good actions, build up options, and learn more—can help guide us in our attempts to positively influence the long term.


Centre for Effective Altruism

The effective altruism community is a global community of people who care deeply about the world, make helping others a significant part of their lives, and use evidence and reason to figure out how best to do so.

80,000 Hours

You have about 80,000 hours in your career: 40 hours per week, 50 weeks per year, for 40 years. This makes your choice of career the most important ethical decision of your life.

Giving What We Can

Giving What We Can is a community of effective givers. We provide the support, community, and information you need to do the most good with your charitable donations.

Forethought Foundation for Global Priorities Research

The Forethought Foundation for Global Priorities Research aims to promote academic work that addresses the question of how to use our scarce resources to improve the world by as much as possible.

Global Priorities Institute

The Global Priorities Institute is an interdisciplinary research centre at the University of Oxford. Our aim is to conduct foundational research that informs the decision-making of individuals and institutions seeking to do as much good as possible.