What We Owe The Future
What's it about
What if the most important people you could help haven't been born yet? This summary explores "longtermism," the radical idea that positively influencing the far future is a key moral priority of our time. You'll discover how your actions today can impact billions of lives to come. Learn how to weigh your impact on future generations and identify the greatest risks to humanity's survival, from pandemics to rogue AI. MacAskill provides a practical framework for making better decisions, so you can contribute to a flourishing, long-lasting future for everyone.
Meet the author
William MacAskill is an Associate Professor in Philosophy at the University of Oxford and a cofounder of the effective altruism movement, which has directed billions toward the world’s most pressing problems. His academic work on how we can best help others led him to a profound realization about the immense impact our actions have on future generations. This perspective, combining rigorous philosophy with a practical drive to do good, provides the foundation for his groundbreaking work on longtermism.
The Script
Think of the last time you made a significant choice—buying a car, choosing a career, even picking a vacation spot. You likely weighed the immediate costs, the benefits to you and your family, and perhaps the impact over the next few years. But what if the most important consequences of our actions aren't the ones we can see, or even the ones that will unfold within our own lifetimes? We operate with a kind of moral nearsightedness, instinctively prioritizing the present and the familiar. This is a deep-seated human tendency. The problem is that this temporal myopia means we are effectively ignoring the overwhelming majority of people who will ever live. Their lives, their potential for happiness or suffering, are rendered invisible by the simple fact that they haven't been born yet. Our entire moral calculus is based on a rounding error.
This profound blind spot is what drove philosopher William MacAskill to re-examine our most basic ethical assumptions. As a co-founder of the effective altruism movement—a global community dedicated to using evidence and reason to do the most good—he noticed a gaping hole in the conversation. While people were optimizing how to help those alive today, almost no one was seriously considering our responsibility to the vast populations of the future. His work at Oxford University's Global Priorities Institute became the intellectual engine for a new way of thinking called longtermism. "What We Owe the Future" is the culmination of years spent grappling with the staggering scale of our potential impact, arguing that safeguarding humanity's future is the most urgent and neglected moral project of our time.
Module 1: The Scale of the Future
The first step is to grasp the sheer scale of what's at stake. MacAskill asks us to perform a thought experiment. Imagine living every human life that has ever existed, one after another. This journey through the past would take about four trillion years. But here's the twist. If humanity survives for even a fraction of the time left until Earth becomes uninhabitable, that four-trillion-year past is just a tiny sliver of the total story. Over 99% of all potential human experience lies in the future. Our moment in time is a tiny fraction of humanity's potential story.
This simple fact reframes everything. It means the future is the main event. So, what does this mean practically? We tend to think of our impact in terms of our immediate community or our own lifetime. But MacAskill suggests we can have predictable, long-term influence. He points to figures like the US Founding Fathers, who designed a constitution to endure for centuries. Or the poet Horace, who wrote with the explicit hope his words would last forever. They did. Their actions have rippled through time, affecting countless lives.
This leads to a crucial insight. Future people have moral significance, regardless of when they are born. The author uses a simple, powerful analogy. If you drop a glass bottle on a hiking trail, it doesn't matter if a child cuts her foot on it tomorrow, next year, or in a century. The harm is the same. The timing is irrelevant. Similarly, the joy and suffering of future people are just as real as our own. Our temporal distance from them doesn't diminish their moral worth. This is an idea we already act on. We build bridges and parks to last for generations. We carefully dispose of radioactive waste. These actions show an implicit belief that the future matters. MacAskill is simply asking us to make this belief explicit and central to our decision-making.