Bostrom was born in 1973 in Helsingborg, Sweden. At a young age, he disliked school, and he ended up spending his last year of high school learning from home. He sought to educate himself in a wide variety of disciplines, including anthropology, art, literature, and science. Despite what has been called a "serious mien", he once did some turns on London's stand-up comedy circuit.
He holds a B.A. in philosophy, mathematics, logic and artificial intelligence from the University of Gothenburg and master's degrees in philosophy and physics, and computational neuroscience from Stockholm University and King's College London, respectively. During his time at Stockholm University, he researched the relationship between language and reality by studying the analytic philosopher W. V. Quine. In 2000, he was awarded a PhD in philosophy from the London School of Economics. He held a teaching position at Yale University (2000–2002), and he was a British Academy Postdoctoral Fellow at the University of Oxford (2002–2005).
Aspects of Bostrom's research concern the future of humanity and long-term outcomes. He introduced the concept of an existential risk, which he defines as one in which an "adverse outcome would either annihilate Earth-originating intelligent life or permanently and drastically curtail its potential." In the 2008 volume Global Catastrophic Risks, editors Bostrom and Milan Ćirković characterize the relation between existential risk and the broader class of global catastrophic risks, and link existential risk to observer selection effects and the Fermi paradox.
In 2005, Bostrom founded the Future of Humanity Institute, which researches the far future of human civilization. He is also an adviser to the Centre for the Study of Existential Risk.
In his 2014 book Superintelligence: Paths, Dangers, Strategies, Bostrom reasoned that with "the creation of a superintelligent being represents a possible means to the extinction of mankind", and "there are actions that can be taken to reduce this risk," such as "the creation of a ‘friendly’ superintelligent being." In January 2015, Bostrom joined Stephen Hawking among others in signing the Future of Life Institute's open letter warning of the potential dangers of AI. The signatories "...believe that research on how to make AI systems robust and beneficial is both important and timely, and that concrete research should be pursued today."
Bostrom has published numerous articles on anthropic reasoning, as well as the book Anthropic Bias: Observation Selection Effects in Science and Philosophy. In the book, he criticizes previous formulations of the anthropic principle, including those of Brandon Carter, John Leslie, John Barrow, and Frank Tipler.
Bostrom believes that the mishandling of indexical information is a common flaw in many areas of inquiry (including cosmology, philosophy, evolution theory, game theory, and quantum physics). He argues that a theory of anthropics is needed to deal with these. He introduced the Self-Sampling Assumption (SSA) and the Self-Indication Assumption (SIA) and showed how they lead to different conclusions in a number of cases. He pointed out that each is affected by paradoxes or counterintuitive implications in certain thought experiments (the SSA in e.g. the Doomsday argument; the SIA in the Presumptuous Philosopher thought experiment). He suggested that a way forward may involve extending SSA into the Strong Self-Sampling Assumption (SSSA), which replaces "observers" in the SSA definition by "observer-moments". This could allow for the reference class to be relativized (and he derived an expression for this in the "observation equation").
In later work, he has described the phenomenon of anthropic shadow, an observation selection effect that prevents observers from observing certain kinds of catastrophes in their recent geological and evolutionary past. Catastrophe types that lie in the anthropic shadow are likely to be underestimated unless statistical corrections are made.
Bostrom's simulation argument posits that at least one of the following statements is very likely to be true:
- The fraction of human-level civilizations that reach a posthuman stage is very close to zero;
- The fraction of posthuman civilizations that are interested in running ancestor-simulations is very close to zero;
- The fraction of all people with our kind of experiences that are living in a simulation is very close to one.
The idea has influenced the views of Elon Musk.
Bostrom is favorable towards "human enhancement", or "self-improvement and human perfectibility through the ethical application of science", as well as a critic of bio-conservative views.
In 1998, Bostrom co-founded (with David Pearce) the World Transhumanist Association (which has since changed its name to Humanity+). In 2004, he co-founded (with James Hughes) the Institute for Ethics and Emerging Technologies, although he is no longer involved in either of these organisations. Bostrom was named in Foreign Policy's 2009 list of top global thinkers "for accepting no limits on human potential."
With philosopher Toby Ord, he proposed the reversal test. Given humans' irrational status quo bias, how can one distinguish between valid criticisms of proposed changes in a human trait and criticisms merely motivated by resistance to change? The reversal test attempts to do this by asking whether it would be a good thing if the trait was altered in the opposite direction.
He has suggested that technology policy aimed at reducing existential risk should seek to influence the order in which various technological capabilities are attained, proposing the principle of differential technological development. This principle states that we ought to retard the development of dangerous technologies, particularly ones that raise the level of existential risk, and accelerate the development of beneficial technologies, particularly those that protect against the existential risks posed by nature or by other technologies.
Bostrom has provided policy advice and consulted for an extensive range of governments and organisations. He gave evidence to the House of Lords, Select Committee on Digital Skills. He is an advisory board member for the Machine Intelligence Research Institute, Future of Life Institute, Foundational Questions Institute and an external advisor for the Cambridge Centre for the Study of Existential Risk.