William MacAskill

William MacAskill (born March 24, 1987) is a Scottish moral philosopher and an associate professor at the University of Oxford who is one of the originators of the Effective Altruism movement. He cofounded its principal organizations, popularized the philosophy of longtermism in his 2022 book What We Owe the Future, and recruited the cryptocurrency entrepreneur Sam Bankman-Fried into the movement's "earning to give" strategy. When Bankman-Fried's FTX exchange collapsed in 2022, MacAskill resigned from the FTX Future Fund advisory board he had helped lead, and the fraud became the central reputational event of his career.¹²

Oxford and the Founding of Effective Altruism

Born William Crouch in Glasgow, MacAskill took a BA in philosophy at Jesus College, Cambridge in 2008 and a BPhil and DPhil at Oxford, completing the doctorate at St Anne's College in 2014 under John Broome and Krister Bykvist. In 2009, as a graduate student, he and the philosopher Toby Ord cofounded Giving What We Can, a society whose members pledge to donate at least ten percent of their income to the most cost-effective charities. In 2011 he cofounded 80,000 Hours, which advises on high-impact careers, with Benjamin Todd, and the two organizations were placed under an umbrella body, the Centre for Effective Altruism, the same year. MacAskill's 2015 book Doing Good Better served as the movement's popular introduction.¹³

Born William Crouch, he and his wife the philosopher Amanda Hall married in 2013 and adopted the surname MacAskill, her grandmother's maiden name; after their 2015 divorce she became Amanda Askell and went on to lead personality-alignment work at Anthropic. The Centre for Effective Altruism and 80,000 Hours were folded under the umbrella charity Effective Ventures, one of the institutions that had to repay FTX money after the collapse, returning 26,786,503 dollars to the bankruptcy estate in 2024 and spinning its constituent projects out as independent legal entities. MacAskill held a post at Oxford's Global Priorities Institute and later joined the research nonprofit Forethought, where in March 2025 he and Fin Moorhouse published "Preparing for the Intelligence Explosion," arguing that AI could compress a century of change into a decade and that society should plan now for the resulting upheavals.⁹¹⁰

Longtermism and What We Owe the Future

MacAskill's work moved with the movement toward longtermism, the view he defined as "the idea that positively influencing the long-term future is a key moral priority of our time." His 2022 book What We Owe the Future argued that because future people vastly outnumber the living, shaping the far future, including by reducing the risk of human extinction from advanced artificial intelligence, is a moral priority of the first order. The book was promoted heavily, with appearances including The Daily Show, and arrived alongside the academic longtermism of Nick Bostrom and the Future of Humanity Institute. MacAskill has stated that he gives away half his income.⁴⁵

The promotional campaign behind What We Owe the Future was unusually expensive for a philosophy book, with a marketing budget reported in the millions of dollars, much of it drawn from effective-altruism funders including the FTX Future Fund. The book reached the New York Times bestseller list, and MacAskill appeared on The Daily Show and on the cover of TIME in August 2022, weeks before FTX collapsed. Critics including the philosopher Émile P. Torres argued that What We Owe the Future downplayed how far the longtermist framework, taken seriously, could license sacrificing present welfare for speculative future populations.⁵¹¹

Recruitment of Sam Bankman-Fried

In 2012 MacAskill spoke at the Massachusetts Institute of Technology, where Bankman-Fried, then a physics undergraduate, heard him present the earning-to-give idea: that a person can do more good by maximizing income and donating it than by direct charitable work. MacAskill advised Bankman-Fried to pursue high-paying quantitative trading, and Bankman-Fried went to Jane Street Capital before founding Alameda Research and FTX. He became the movement's largest single funder. MacAskill served as an unpaid adviser to the FTX Future Fund, announced in 2022, which directed FTX money to longtermist and AI-safety causes.⁶⁷

MacAskill stayed close to Bankman-Fried as the fortune grew. He introduced Bankman-Fried to Elon Musk in 2022 in an attempt to interest the entrepreneur in a joint bid for Twitter, a text exchange that surfaced in the discovery for Musk's later Twitter litigation. After the collapse, federal prosecutors named MacAskill in court filings as one of the public figures Bankman-Fried had cultivated, and the Future Fund's leadership conceded it had relied on a benefactor whose business it did not scrutinize.⁷¹¹

The FTX Collapse and Fallout

A March 2023 TIME investigation reported that effective-altruism leaders, MacAskill among them, had been warned about Bankman-Fried's conduct years before the collapse. When FTX failed in November 2022, the entire Future Fund team, including Nick Beckstead and Leopold Aschenbrenner, resigned, stating they had been "shocked" and condemning any deception by FTX leadership "in the strongest possible terms." Bankman-Fried was convicted of fraud in November 2023. The episode destroyed the movement's largest funding source, drew scrutiny to MacAskill's role in shaping Bankman-Fried's worldview, and discredited effective altruism's public standing.²⁸

The TIME account stated that figures connected to the movement, including the entrepreneurs Tara Mac Aulay and others who had worked with Bankman-Fried at Alameda Research in 2018, had raised concerns about his honesty and management directly to MacAskill years before FTX's rise. MacAskill issued a public statement after the collapse saying that if Bankman-Fried's conduct was as alleged he had been "completely deceived," that he felt "blindsided," and that the fraud betrayed everything effective altruism stood for. He largely withdrew from public commentary for a period before re-emerging through Forethought to focus on the governance of advanced AI rather than on the cause-prioritization and earning-to-give framing he had built the movement on.⁸¹¹