Anthropic Bias: Observation Selection Effects in Science and Philosophy
Nick Bostrom (New York: Routledge, 2002)
On its fourth print run. Reviews below.
Buy from e.g. Amazon.com ($79,96)
Read sample: first five chapters + bibliography [pdf]
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Some reviews
Review by Wouter Meijs, Studies In History and Philosophy of Science Part B: Studies In History and Philosophy of Modern Physics, Vol. 36, No. 3, pp. 586-589 (2005)
"From traffic analysis via a many-worlds interpretation of quantum mechanics and the problem of the fine-tuning of the universe to the purely philosophical problems of the Doomsday argument and the Sleeping Beauty problem, Bostrom succeeds in shining a new and interesting light on all of these issues."
Review by Christian Wuthrich, Philosophy of Science, Vol. 71, No. 2, pp. 230-232 (2004)
"Bostrom presents a highly readable and widely relevant work which can be warmly recommended to everyone in philosophy of science. ... Bostrom’s book has appeared in the Studies in Philosophy: Outstanding Dissertations series edited by the late Robert Nozick. Just a few pages into the volume, and the reader learns why."
Review by Milan Cirkovic, Foundations of Science, Vol. 8, No. 4, pp. 417-423 (2003)
"Probably the worst thing one can say about this book is that it is too short.... Anthropic Bias is a wonderful achievement, which belongs on the shelf of every serious student of modern cosmology and philosophy of science."
Review by Neil Manson, Notre Dame Philosophical Reviews, 2003.02.09.
"Anthropic Bias is a synthesis of some of the most interesting and important ideas to emerge from discussion of cosmic fine-tuning, the anthropic principle, and the Doomsday Argument. It deserves a place on the shelves of epistemologists and philosophers of science, as well as specialists interested in the topics just mentioned."
Review by Milan Cirkovic, Foundations of Physics, Vol. 32, No. 11, November 2002
"A wonderful achievement"
Sample chapters
Chapters 1-5, plus front matter, bibliography and index [pdf]
... This book explores how to reason when you suspect that your evidence is biased by observation selection effects. An explanation of what observation selection effects are has to await chapter 1. Suffice it to say here that the topic is intellectually fun, difficult, and important. We will be discussing many interesting applications: philosophical thought experiments and paradoxes aside, we will use our results to address several juicy bits of contemporary science: cosmology (how many universes are there?), evolution theory (how improbable was the evolution of intelligent life on our planet?), the problem of time's arrow (can it be given a thermodynamic explanation?), game theoretic problems with imperfect recall (how to model them?), traffic analysis (why is the "next lane" faster?) and a lot more - the sort of stuff that intellectually active people like to think about
Contents
ACKNOWLEDGEMENTS.......... xi
PREFACE.......... xiii
CHAPTER 1
INTRODUCTION.......... 1
Observation selection effects.......... 1
A brief history of anthropic reasoning.......... 5
Synopsis of this book.......... 7CHAPTER 2
FINE-TUNING IN COSMOLOGY.......... 11
Does fine-tuning need explaining?.......... 13
No Inverse Gamblers Fallacy.......... 16
Roger White and Phil Dowes analysis.......... 18
Surprising vs. unsurprising improbable events.......... 23
Modeling observation selection effects: the angel parable.......... 32
Preliminary conclusions.......... 39CHAPTER 3
ANTHROPIC PRINCIPLES: THE MOTLEY FAMILY.......... 43
The anthropic principle as expressing an observation
selection effect.......... 43
Anthropic hodgepodge.......... 46
Freak observers and why earlier formulations are inadequate.......... 51
The Self-Sampling Assumption.......... 57CHAPTER 4
THOUGHT EXPERIMENTS SUPPORTING THE
SELF-SAMPLING ASSUMPTION.......... 59
The Dungeon gedanken.......... 59
Two thought experiments by John Leslie.......... 62
The Incubator gedanken.......... 64
The reference class problem.......... 69CHAPTER 5
THE SELF-SAMPLING ASSUMPTION IN SCIENCE.......... 73
SSA in cosmology.......... 73
SSA in thermodynamics.......... 76
SSA in evolutionary biology.......... 78
SSA in traffic analysis.......... 82
SSA in quantum physics.......... 84
Summary of the case for SSA.......... 86CHAPTER 6
THE DOOMSDAY ARGUMENT.......... 89
Background.......... 89
Doomsayer Gott.......... 90
The incorrectness of Gotts argument.......... 92
Doomsayer Leslie.......... 94
The premisses of DA, and the Old evidence problem.......... 96
Leslies views on the reference class problem.......... 104
Alternative conclusions of DA.......... 107CHAPTER 7
INVALID OBJECTIONS AGAINST THE DOOMSDAY ARGUMENT.......... 109
Doesnt the Doomsday argument fail to
target the truth?.......... 109
The baby-paradox.......... 111
Isnt a sample size of one too small?.......... 115
Couldnt a Cro-Magnon man have used the
Doomsday argument?.......... 116
We can make the effect go away simply by considering
a larger hypothesis space.......... 116
Arent we necessarily alive now?.......... 118
Sliding reference of soon and late?.......... 119
How could I have been a 16th century human?.......... 119
Doesnt your theory presuppose that what happens in causally
disconnected regions affects what happens here?.......... 120
But we know so much more about ourselves than
our birth ranks!.......... 120
The Self-Indication Assumption
Is there safety in numbers?.......... 122CHAPTER 8
OBSERVER-RELATIVE CHANCES IN ANTHROPIC REASONING?.......... 127
Leslies argument, and why it fails.......... 127
Observer-relative chances: another go.......... 130
Discussion: indexical factsno conflict with physicalism.......... 132
In conclusion.......... 136
Appendix: the no-betting results.......... 137CHAPTER 9
PARADOXES OF THE SELF-SAMPLING ASSUMPTION.......... 141
The Adam & Eve experiments.......... 142
Analysis of Lazy Adam: predictions and counterfactuals.......... 144
The UN++ gedanken: reasons and abilities.......... 150
Quantum Joe: SSA and the Principal Principle.......... 154
Upshot.......... 156
Appendix: The Meta-Newcomb problem.......... 157CHAPTER 10
OBSERVATION SELECTION THEORY: A METHODOLOGY FOR
ANTHROPIC REASONING.......... 159
Building blocks, theory constraints and desiderata.......... 159
The outline of a solution.......... 161
SSSA: Taking account of indexical information of observermoments..........162
Reassessing Incubator.......... 165
How the reference class may be observer-moment relative.......... 168
Formalizing the theory: the Observation Equation.......... 172
A quantum generalization of OE.......... 174
Non-triviality of the reference class: why R0 must be rejecte..........175
A subjective factor in the choice of reference class?.......... 181CHAPTER 11
OBSERVATION SELECTION THEORY APPLIED.......... 185
Cosmological theorizing: fine-tuning and freak observers.......... 185
The freak-observer problem places only lax demands on
the reference class.......... 193
The Sleeping Beauty problem: modeling imperfect recall.......... 194
The case of no outsiders.......... 195
The case with outsiders.......... 196
Synthesis of the 1/2- and the 1/3-views.......... 198
Observation selection theory applied to other scientific problems.......... 198
Robustness of reference class and scientific solidity.......... 202
Wrap-up.......... 204BIBLIOGRAPHY.......... 207
INDEX.......... 219