Ever since Copernicus, scientists have continually adjusted their view of human nature, moving it further and further from its ancient position at the center of Creation. But in recent years, a startling new concept has evolved that places it more firmly than ever in a special position. Known as the Anthropic Cosmological Principle, this collection of ideas holds that the existence of intelligent observers determines the fundamental structure of the Universe. In its most radical version, the Anthropic Principle asserts that (...) "intelligent information-processing must come into existence in the Universe, and once it comes into existence, it will never die out." This wide-ranging and detailed book explores the many ramifications of the Anthropic Cosmological Principle, covering the whole spectrum of human inquiry from Aristotle to Z bosons. Bringing a unique combination of skills and knowledge to the subject, John D. Barrow and Frank J. Tipler--two of the world's leading cosmologists--cover the definition and nature of life, the search for extraterrestrial intelligence, and the interpretation of the quantum theory in relation to the existence of observers. The book will be of vital interest to philosophers, theologians, mathematicians, scientists, and historians, as well as to anyone concerned with the connection between the vastness of the universe of stars and galaxies and the existence of life within it on a small planet out in the suburbs of the Milky Way. (shrink)

_Anthropic Bias_ explores how to reason when you suspect that your evidence is biased by "observation selection effects"--that is, evidence that has been filtered by the precondition that there be some suitably positioned observer to "have" the evidence. This conundrum--sometimes alluded to as "the anthropic principle," "self-locating belief," or "indexical information"--turns out to be a surprisingly perplexing and intellectually stimulating challenge, one abounding with important implications for many areas in science and philosophy. There are the philosophical thought experiments and paradoxes: (...) the Doomsday Argument; Sleeping Beauty; the Presumptuous Philosopher; Adam & Eve; the Absent-Minded Driver; the Shooting Room. And there are the applications in contemporary science: cosmology ; evolutionary theory ; the problem of time's arrow ; quantum physics ; game-theory problems with imperfect recall ; even traffic analysis. _Anthropic Bias_ argues that the same principles are at work across all these domains. And it offers a synthesis: a mathematically explicit theory of observation selection effects that attempts to meet scientific needs while steering clear of philosophical paradox. (shrink)

In the form in which it was originally expounded, the anthropic principle was presented as a warning to astrophysical and cosmological theorists of the risk of error in the interpretation of astronomical and cosmological information unless due account is taken of the biological restraints under which the information was acquired. However, the converse message is also valid: biological theorists also run the risk of error in the interpretation of the evolutionary record unless they take due heed of the astrophysical restraints (...) under which evolution took place. After an introductory discussion of the ordinary ('weak') anthropic principle and of its more contestable ('strong') analogue, a new application of the former to the problem of the evolution of terrestrial life is presented. It is shown that the evidence suggests that the evolutionary chain included at least one but probably not more than two links that were highly improbable (a priori) in the available time interval. (shrink)

Analyzes the nature of international disagreements and conflict resolution in terms of game theory and non-zero-sum games.

Humanity seems to have a bright future, i.e., a non-trivial chance of expanding to fill the universe with lasting life. But the fact that space near us seems dead now tells us that any given piece of dead matter faces an astronomically low chance of begating such a future. There thus exists a great filter between death and expanding lasting life, and humanity faces the ominous question: how far along this filter are we?

Tn this paper I explore and to an extent defend HS. The main philosophical challenges to HS come from philosophical views that say that nomic concepts-laws, chance, and causation-denote features of the world that fail to supervene on non-nomic features. Lewis rejects these views and has labored mightily to construct HS accounts of nomic concepts. His account of laws is fundamental to his program, since his accounts of the other nomic notions rely on it. Recently, a number of philosophers have (...) criticized Lewis's account, and Humean accounts of laws generally, for delivering, at best, a pale imitation ofthe genuine item. These philosophers think that the notion of law needed by science requires laws-if there are any-to be fundamental features of our world that are completely distinct from and not supervenient on the particular facts that they explain. I side with Lewis against these philosophers. Here I will argue that although Lewis-laws don't fulfill all our philosophical expectations, they do play the roles that science needs laws to play. The metaphysics and epistemology of Humean laws, and more specifically, Lewis-laws, are in much better shape than the metaphysics and epistemology of the main anti-Humean alternatives. However, I do have inisgivings about Lewis's account. Both he and his critics assume that the basic properties are so individuated so that the laws are not metaphysically necessary. If this assumption is rejected, then the question of Humean supervenience lapses. I conclude with a brief discussion of this position. (shrink)

"[This book] proposes new foundations for the Bayesian principle of rational action, and goes on to develop a new logic of desirability and probabtility."—Frederic Schick, _Journal of Philosophy_.

This is the second volume of philosophical essays by one of the most innovative and influential philosophers now writing in English. Containing thirteen papers in all, the book includes both new essays and previously published papers, some of them with extensive new postscripts reflecting Lewis's current thinking. The papers in Volume II focus on causation and several other closely related topics, including counterfactual and indicative conditionals, the direction of time, subjective and objective probability, causation, explanation, perception, free will, and rational (...) decision. Throughout, Lewis analyzes global features of the world in such a way as to show that they might turn out to supervene on the spatiotemporal arrangement of local qualities. (shrink)

Attempts to model interstellar colonization may seem hopelessly compromised by uncertainties regarding the technologies and preferences of advanced civilizations. If light speed limits travel speeds, however, then a selection effect may eventually determine frontier behavior. Making weak assumptions about colonization technology, we use this selection effect to predict colonists’ behavior, including which oases they colonize, how long they stay there, how many seeds they then launch, how fast and far those seeds fly, and how behavior changes with increasing congestion. This (...) colonization model explains several astrophysical puzzles, predicting lone oases like ours, amid large quiet regions with vast unused resources. (shrink)

John Leslie presents a thought experiment to show that chances are sometimes observer-relative in a paradoxical way. The pivotal assumption in his argument – a version of the weak anthropic principle – is the same as the one used to get the disturbing Doomsday argument off the ground. I show that Leslie's thought experiment trades on the sense/reference ambiguity and is fallacious. I then describe a related case where chances are observer-relative in an interesting way. But not in a paradoxical (...) way. The result can be generalized: At least for a very wide range of cases, the weak anthropic principle does not giverise to paradoxical observer-relative chances. This finding could be taken to give new indirect support to the doomsday argument. (shrink)

Transhumanism is a loosely defined movement that has developed gradually over the past two decades. [1] It promotes an interdisciplinary approach to understanding and evaluating the opportunities for enhancing the human condition and the human organism opened up by the advancement of technology. Attention is given to both present technologies, like genetic engineering and information technology, and anticipated future ones, such as molecular nanotechnology and artificial intelligence.

_This paper outlines the case for believing that we will have superhuman artificial intelligence_ _within the first third of the next century. It looks at different estimates of the processing power of_ _the human brain; how long it will take until computer hardware achieve a similar performance;_ _ways of creating the software through bottom-up approaches like the one used by biological_ _brains; how difficult it will be for neuroscience figure out enough about how brains work to_ _make this approach work; (...) and how fast we can expect superintelligence to be developed once_ _there is human-level artificial intelligence._. (shrink)

Computers have far to go to match human strengths, and our estimates will depend on analogy and extrapolation. Fortunately, these are grounded in the first bit of the journey, now behind us. Thirty years of computer vision reveals that 1 MIPS can extract simple features from real-time imagery--tracking a white line or a white spot on a mottled background. 10 MIPS can follow complex gray-scale patches--as smart bombs, cruise missiles and early self-driving vans attest. 100 MIPS can follow moderately unpredictable (...) features like roads--as recent long NAVLAB trips demonstrate. 1,000 MIPS will be adequate for coarse-grained three-dimensional spatial awareness--illustrated by several mid-resolution stereoscopic vision programs, including my own. 10,000 MIPS can find three-dimensional objects in clutter--suggested by several "bin-picking" and high-resolution stereo-vision demonstrations, which accomplish the task in an hour or so at 10 MIPS. The data fades there--research careers are too short, and computer memories too small, for significantly more elaborate experiments. (shrink)

Are we in imminent danger of extinction? Yes, we probably are, argues John Leslie in his chilling account of the dangers facing the human race as we approach the second millenium. The End of the World is a sobering assessment of the many disasters that scientists have predicted and speculated on as leading to apocalypse. In the first comprehensive survey, potential catastrophes - ranging from deadly diseases to high-energy physics experiments - are explored to help us understand the risks. One (...) of the greatest threats facing humankind, however, is the insurmountable fact that we are a relatively young species, a risk which is at the heart of the 'Doomsday Argument'. This argument, if correct, makes the dangers we face more serious than we could have ever imagined. This more than anything makes the arrogance and ignorance of politicians, and indeed philosophers, so disturbing as they continue to ignore the manifest dangers facing future generations. (shrink)

The pace of scientific progress may be hindered by the tendency of our academic institutions to reward being popular rather than being right. A market-based alternative, where scientists can more formally 'stake their reputation', is presented here. It offers clear incentives to be careful and honest while contributing to a visible, self-consistent consensus on controversial scientific questions. In addition, it allows patrons to choose questions to be researched without choosing people or methods. The bulk of this paper is spent in (...) examining potential problems with the proposed approach. After this examination, the idea still seems to be plausible and worthy of further study. (shrink)

If we are not to conclude that most planets like Earth have evolved life as intelligent as we are, we must presume Earth is not random. This selection effect, however, also implies that the origin of life need not be as easy as the early appearance of life on Earth suggests. If a series of major evolutionary transitions were required to produce intelligent life, selection implies that a subset of these were “critical steps,” with durations that are similarly distributed. The (...) time remaining from now until simple life is no longer possible on Earth must also be similarly distributed. I show how these results provide timing tests to constrain models of critical evolutionary transitions. (shrink)

A recent paper by Korb and Oliver in this journal attempts to refute the Carter-Leslie Doomsday argument. I organize their remarks into five objections and show that they all fail. Further efforts are thus called upon to find out what, if anything, is wrong with Carter and Leslie's disturbing reasoning. While ultimately unsuccessful, Korb and Oliver's objections do however in some instances force us to become clearer about what the Doomsday argument does and doesn't imply.

Evolutionary development is sometimes thought of as exhibiting an inexorable trend towards higher, more complex, and normatively worthwhile forms of life. This paper explores some dystopian scenarios where freewheeling evolutionary developments, while continuing to produce complex and intelligent forms of organization, lead to the gradual elimination of all forms of being that we care about. We then consider how such catastrophic outcomes could be avoided and argue that under certain conditions the only possible remedy would be a globally coordinated policy (...) to control human evolution by modifying the fitness function of future intelligent life forms. (shrink)

The purpose of this paper, boldly stated, is to propose a new type of philosophy, a philosophy whose aim is prediction. The pace of technological progress is increasing very rapidly: it looks as if we are witnessing an exponential growth, the growth-rate being proportional to the size already obtained, with scientific knowledge doubling every 10 to 20 years since the second world war, and with computer processor speed doubling every 18 months or so. It is argued that this technological development (...) makes urgent many empirical questions which a philosopher could be well-suited to help answering. I try to cover a broad range of interesting problems and approaches, which means that I won't go at all deeply into any of them; I only try to say enough to show what some of the problems are, how one can begin to work with them, and why philosophy is relevant. My hope is that this will whet your appetite to deal with these questions, or at least increase general awareness that they worthy tasks for first-class intellects, including ones which might belong to philosophers. (shrink)

Human behavior regarding medicine seems strange; assumptions and models that seem workable in other areas seem less so in medicine. Perhaps we need to rethink the basics. Toward this end, I have collected many puzzling stylized facts about behavior regarding medicine, and have sought a small number of simple assumptions which might together account for as many puzzles as possible.

The Doomsday argument purports to show that the risk of the human species going extinct soon has been systematically underestimated. This argument has something in common with controversial forms of reasoning in other areas, including: game theoretic problems with imperfect recall, the methodology of cosmology, the epistemology of indexical belief, and the debate over so-called fine-tuning arguments for the design hypothesis. The common denominator is a certain premiss: the Self-Sampling Assumption. We present two strands of argument in favor of this (...) assumption. Through a series of thought experiments we then investigate some bizarre prima facie consequences – backward causation, psychic powers, and an apparent conflict with the Principal Principle. (shrink)