Nick Bostrom's home page

Looking very serious now... Welcome! This page will tell you something about me and my goals. You will also find a selection of my writings in philosophy of science, ethics, transhumanism, probability theory and more, plus a work of poetry in Swedish which you will be unable to read.

(c) Nick Bostrom, PhD
Oxford University, Research Fellow
Selected writings


Anthropic Bias: Observation Selection Effects in Science and Philosophy (Academic/Nick's Pick) This book presents the first mathematically explicit theory of observation selection effects - an important kind of bias that infests many branches of science and philosophy. But we can tame them! There are implications for cosmology, evolutionary biology, the interpretation of quantum mechanics, the Doomsday argument, the Sleeping Beauty problem, the search for extraterrestrial life, the question of whether God exists, and traffic planning. There is not too much math and the results are explained verbally also. I've negotiated the right to make five sample chapters available online. [Routledge, New York, 2002]

Self-Locating Belief in Big Worlds: Cosmology's Missing Link to Observation (Academic/Nick's Pick) NEW Current cosmological theories say that the world is so big that all possible observations are in fact made. But then, how can we test them? What could count as negative evidence? - To answer that, we need to take into account observation selection effects. [Penultimate draft of paper Journal of Philosophy, 2002, Vol. 99, No. 12.]. [pdf | doc]

Cars In the Other Lane Really Do Go Faster (Popular/Nick's Pick) When driving on the motorway, have you ever wondered about (and cursed) the fact that cars in the other lane seem to be getting ahead faster than you? You might be inclined to account for this by invoking Murphy's Law ("If anything can go wrong, it will", discovered by Edward A. Murphy, Jr, in 1949). But there is a deeper explanation, based on observational selection effects... [PLUS, 2001, No. 17]

The Doomsday Argument, Adam & Eve, UN++, and Quantum Joe (Academic) On the Doomsday argument and related paradoxes. [Penultimate draft of paper in Synthese, 2001, Vol. 127, No. 3, pp. 359-387]. [pdf | doc]

The Super-Newcomb Problem (Academic) A puzzling variant of the Newcomb puzzle. [Analysis, 2001, Vol. 61, No. 4., pp. 309-310. [pdf | doc]

A Primer on the Doomsday argument (Popular) The Doomsday argument purports to prove, from basic probability theory and a few seemingly innocuous empirical premisses, that the risk that our species will go extinct soon is much greater than previously thought. (My view is that the Doomsday argument is inconclusive - although not for any trivial reason. In my book, I argue that a theory of observation selection effects is needed to truly explain what goes wrong.) [Colloquia Manilana (PDCIS), 1999, Vol. 7; reprinted in The Actuary, March 2001, and in ephilosopher.com, 2001]

The Doomsday argument and the Self-Indication Assumption: Reply to Olum (Academic) NEW Argues against Olum and the Self-Indication Assumption. Co-authored with Milan M. Cirkovic. [Penultimate draft forthcoming in Philosophilcal Quarterly] [pdf]

The Mysteries of Self-Locating Belief and Anthropic Reasoning (Academic) NEW Summary of some of the difficulties that a theory of observation selection effects faces and a solution sketch. [Harvard Review of Philosophy, forthcoming] [pdf]

Beyond the Doomsday Argument: Reply to Sowers and Further Remarks (Academic) NEW Argues against George Sower's refutation of the doomsday argument, and outlines what I think is the real flaw.

The Doomsday Argument is Alive and Kicking (Academic) Have Korb and Oliver refuted the doomsday argument? No. [Penultimate draft of a paper in Mind, 1999, Vol.108, No.431, pp. 539-550]

Observer-relative chances in anthropic reasoning? (Academic) A paradoxical thought experiment [Penultimate draft of paper in Erkenntnis, 2000, Vol. 52, pp. 93-108]

Cosmological Constant and the Final Anthropic Hypothesis (Academic) Examines the implications of recent evidence for a cosmological constant for the prospects of indefinite information processing in the multiverse. Co-authored with Milan M. Cirkovic; several formats available at the physics preprints archive. [Astrophysics and Space Science, 2000, Vol. 279, No. 4, pp. 675-687]

(For many more papers related to the anthropic reasoning, by me and others, please visit anthropic-principle.com)


Astronomical Waste: The Opportunity Cost of Delayed Technological Development (Academic) NEW Suns are illuminating and heating empty rooms, unused energy is being flushed down black holes, and our great common endowment of negentropy is being irreversibly degraded into entropy on a cosmic scale. These are resources that an advanced civilization could have used to create value-structures, such as sentient beings living worthwhile lives... [Penultimate draft of paper forthcoming in Utilitas] [html | pdf]

Desire, Time, and Ethical Weight (Academic) Discusses the role of time in desire-satisfactionism. E.g. is it more important that a desire gets satisfied if it has been held longer? Do past desires count? (I think this paper will need some serious revising.) [pdf]

Human Genetic Enhancements: A Transhumanist Perspective (Academic) NEW A transhumanist ethical framework for public policy regarding genetic enhancements, particularly human germ-line genetic engineering [Penultimate draft of paper forthcoming in The Journal of Value Inquirery[ html | pdf] [Note: newest version only in pdf.]

Transhumanist Ethics (Academic/Popular) Proposes a transhumanist axiology and applies it to human germ-line engineering (the latter bit is mostly taken from the foregoing paper). [pdf]


The World in 2050 (Popular) Features an imaginary dialogue, set in 2050 and broadcast in virtual reality, in which three polymaths debate various issues that their society is facing.

The Transhumanist FAQ (Popular/Nick's Pick) 50+ persons collaborated with me in attempting to lay the foundations for a transhumanist worldview [also in German, Hungarian, Dutch, and Italian].

Existential Risks: Analyzing Human Extinction Scenarios and Related Hazards (Popular/Academic/Nick's Pick) Existential risks are ways in which we could screw up badly and permanently. Interestingly, there is more scholarly work on the life-habits of the dung fly than on existential risk. In other words, an opportunity to make a contribution, perhaps. Of course, the point is not to welter in doom and gloom but to get a better understanding of where the main pitfalls are so we can develop workable strategies for not falling into them. [also in pdf-format; Journal of Evolution and Technology, 2002, vol. 9]

How long before superintelligence? (Academic) This short paper, now a few years old, presents the case for thinking that we might well have superhuman artificial intelligence within the first third of this century. [Updated version of the original in Int. Jour. of Future Studies, 1998, vol. 2]

When Machines Outsmart Humans (Popular) This slightly more recent article briefly reviews the argument set out in the previous one, and also explains four immediate consequences of human-level machine intelligence. [Forthcoming in Futures, 2003, as the target paper of a symposium, toghether with a reply to five other papers that comment on it.]

Are You Living in a Computer Simulation? (Popular/Academic/Nick's Pick) NEW This paper argues that at least one of the following propositions is true: (1) the human species is very likely to go extinct before reaching the posthuman stage; (2) any posthuman civilization is extremely unlikely to run significant number of simulations or (variations) of their evolutionary history; (3) we are almost certainly living in a computer simulation. It follows that the nave transhumanist dogma that there is a significant chance that we will one day become posthumans who run ancestor-simulations is false, unless we are currently living in a simulation. A number of other consequences of this result are also discussed. [Penultimate draft of paper in Philosophical Quarterly, 2003, Vol. 53, No. 211, pp. 243-255]. [pdf | html]

HALF-BAKED (working-papers at various stages of incompletion)

The Future of Human Evolution (Popular) Evolution doesn't always go in the direction of what we would regard as more valuable life-forms. What lies in store for our species? [pdf | html | doc]

Ethics for Intelligent Machines: A Proposal (Academic/Popular) Some guidelines [pdf | html | doc]

Transhumanist Values (Academic/Popular) Values, perhaps, are fluffy cloudy things. This paper attempts to sketch some transhumanist values.

What is a singleton? (Popular) Concept describing a kind of social structure.


Nanotechnology Now. (Popular) On nanotechnology, progress, and transhumanism. (December 2001).

Nanomagazine.com. (Popular) On AI and nanotechnology. (October 2001).

Resonance Publications. (Popular) On philosophy, transhumanism, education, and government. On nanotechnology, progress, and transhumanism. (March 2000).

Heart of the Matter, BBC1 Television. (Popular) Script: "Against Aging". (March 2000).


Synkrotron (Popular) The final fruit and crowning completion of my earlier efforts as a practicing poet. All in Swedish! As a bonus, your browser probably won't display the last three letters of the Swedish alphabet. I've quit writing poetry; "for more there is no need."


Human Reproductive Cloning from the Perspective of the Future. (Popular) NEW. Boy have I been asked the cloning question waaay too many times! But here is an updated statement of 27 Dec 2002. (An older version can be found here.)

The Epistemological Mystique of Self-Locating Belief (Academic) Intriguing, eh?

What is transhumanism? (Popular) An older introduction but with a new postscript. [Earlier version in Sawaal, August 2000; reprinted in Doctor Tandy's First Guide to Life Extension and Transhumanity, 2001, Ria University Press, Palo Alto]

Predictions from Philosophy? (Popular) How analytical philosophers could help forecast our technological future. Argues that academic philosophers can do something useful if they become scientific generalists, polymaths, with a thorough grounding in several sciences. Also contains specific remarks about the Fermi paradox, superintelligence, sociological attractors and other things. [Colloquia Manilana (PDCIS), 2000, Vol. 7]

What to say to the Skeptic (Academic) A discussion, in dialog form, of the position of the radical skeptic, who doubts that any inductive knowledge is possible. Very early work.

Cortical Integration (Academic) Possible Solutions to the Binding and Linking Problems in Perception, Reasoning and Long Term Memory. (My MSc-thesis in computational neuroscience on the problem of finding neurologically plausible dynamical binding mechanisms in the brain for producing and storing structured representations.) [Consciousness and Cognition, 2000, Vol. 9, No. 2, pp. 39S-40S]

Mailing list postings. (Popular) I post occasionally to some lists. I've edited and html-ized one particularly long thread on the extropians list from a few years ago, on the topic of how to avoid nanotechnological disaster, here.

Understanding Quine's Theses of Indeterminacy (Academic) (My MA-thesis in philosophy. Boring.

Fine-Tuning Arguments in Cosmology (Academic) Our universe appears to be fine-tuned for intelligent life. There are several physical constants such that had they been even a teeny, weeny bit different than they are, then life could not have existed. Why is the world like that? Some people think this improbable coincidence points to the existence Designer. Others shrug it off as one of those brute facts that just happen to obtain. Others still suggest that a multiverse theory (where our universe is just one out of very many physically real universes) can explain the phenomenon. Nick investigates. [Has become chapter 2 of the book] [pdf]

Observational Selection Effects and Probability (Academic) Doctoral dissertation, which presented the first mathematically explicit "observation selection theory", with implications in cosmology, evolutionary biology, the interpretation of quantum mechanics, the search for extraterrestrial life, to the question of whether God exists, and for traffic planning. It has now been transfigured into a book.

What's new?
My first book came out last summer: Anthropic Bias: Observation Selection Effects in Science and Philosophy. Five sample chapters are available from the book's webpage.
Several new papers have been completed and added to this page (see left column). The one on the Simulation Argument has attracted attention. For philosophy of science people, I would point to the one on Self-Location in Big Worlds (as well as the book). Activists may check out the Existential Risks paper. The paper Astronimical Waste is also spanking NEW .

An updated statement on cloning, "Human Reproductive Cloning from the Perspective of the Future".

In January this year I relocated to Oxford to become a British Academy Postdoctoral Fellow and a member of the philosophy faculty. The previous two and a half year I was a Lecturer at Yale. I expect to stay in Oxford for at least the next three years. (For my new address and phone number, please see farther down this column.)

My CV is updated and contains a list of Publications and Media appearances.

I'm a whole year older than I was merely twelve months ago. [Added March 10, 2003: Today it finally happened, I became 30, i.e. middle-aged. Imagine all the things that I am now officially too old to do.]

Who is this Bostrom anyway?

Cheesy as it sounds, I want inter alia to make the world a better place.

How? For me, I think the best way to contribute is by thinking about how anticipated future technologies can be turned to human good, and to help others who are also working to do that.

Why? Things are moving quite fast. There is a chance that we will have molecular manufacturing or superhuman artificial intelligence within the first half of this century. This prospect carries big promises and dangers. In a worst-case scenario, intelligent life could go extinct. Alternatively, if we play it nice and smart, you and I or our descendants might manage to make the leap and become "posthumans" -- beings with much greater health-span and vastly enhanced intellectual, emotional, physical, and social capacities. Humans are great and we have the potential to develop into something even greater. Some are anxious about tampering with nature, especially human nature. We need to tread carefully and hold each other's hands as we walk this path. But imagine a world without involuntary suffering, aging and disease... We're set on a journey that can ultimately take us into whole new realms of wonderful ways of being, thinking, feeling, and relating to each other. Some of our finest dreams can come true. In order for that to happen, we must grow up, and that may entail shedding some of our current biological limitations. I hope that as many as possible of us who are currently alive will get the opportunity to truly grow up and experience life as it should have been all along.

It is high time to do some serious thinking on this subject. Many difficult ethical, strategic, technical, social, personal and cultural issues have to be addressed to make the vision a reality. To try encourage research and public debate, I co-founded the not-for-profit World Transhumanist Association in early 1998. It currently has over 2,000 members from all walks of life and from all 'round the world. The WTA holds conferences, publishes the scholarly Journal of Evolution and Technology, the popular Transhumanity Magazine, runs mailinglists and discussion groups, helps organize local chapters, and other things of that sort. The work is being done by men and women who care enough about the future to offer their time and effort for no other reward than to be taking part in making it happen. The real heroes of grassroots movements are often known to only a handful of colleagues.

As for my own research interests, they should be obvious from the texts and links on this page. I work mainly in philosophy of science, foundations of probability theory, ethics, and on transhumanism. My background is in physics, computational neuroscience, mathematical logic, philosophy, AI and some psychology. In my undergraduate days I was doing three full-time programs and one half-time program simultaneously, setting what to the best of my knowledge constitutes a Swedish record in nerdiness. (Mention of these facts was commanded by the principle of understated modesty, which I try to scrupulously obey throughout this page.)

In earlier phases of my life, I've been an artist and a poet. I was also doing stand-up comedy for a while on the vibrant London circuit, partly in order to live life to its fullest and partly to explore a different way of communicating. Comedy breaks down our walls of prejudice. But above all, it was a lot of fun. Comedy-pals, please don't go on citing the infamous "rainbows are motherf*****s" line out of context as it can be all too easily be misconstrued outside of its revolutionary negotiated postmodern subversive quantum-metaphysical radical ontologico-semantic dialectic aquatic ornithological textuality!

Three reasons for making aging a favorite complaint

1. The weather is only bad some of the time but one is always getting older.

2. By whining now, one might already have discounted the bad when it happens.

3. On a serious note, aging causes an enormous amount of human suffering (more than all the wars in human history). Some are complacent about aging because members of our species have always aged and because it's "natural". Those are really bad apologies which will be forgotten when we find a cure. Extending human health-span is just one part of the transhumanist project. But we need to stay alive to see the rest!

Virtual Estate

Material on observational selection effects
The World Transhumanist Association
Devoted to the question, Are you living in a computer simulation?
The Journal of Evolution and Technology

Email: [email protected]
Phone: (+44) 7798 - 74 42 42
Fax: (+44) 1865 - 276932
Nick Bostrom
Harris Manchester College
Mansfield Road
Oxford, OX1 3TD, United Kingdom

(To enroll in a seminar on how to avoid rip-offs, simply send five easy payments of $89.95 to the above address.)

Hmm... What's beyond the horizon?

The ball is in our hands! (Courtesy BBC)

If you like this page, tell all your friends about it.

Ok, if you've made it all the way down here, we're family more or less. So if you will forgive...ahem...

ON the bank at the end
Of what was there before us
Gazing over to the other side
On what we can become
Veiled in the mist of nave speculation
We are busy here preparing
Rafts to carry us across
Before the light goes out leaving us
In the eternal night of could-have-beens