Anthropic Bias Observation Selection Effects in Science and Philosophy Nick Bostrom
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Observation selection effectsI submit that the only way to get a plausible model of how to reason from fine-tuning is by explicitly taking observation selection effects into account. This section will outline parts of such a theory. Later chapters will expand and support themes that are merely alluded to here. A theory of observation selection effects has applications in many domains. In this section we focus on applications in cosmology. As before, let “  ” rigidly denote our universe. We know some things K about (it’s life-permitting; it contains the Eiffel tower; it’s quite big etc.). Let hM be the multiverse hypothesis; let hD be the design hypothesis; and let hC be the chance hypothesis. In order to determine what values to assign to the conditional probabilities P(hM|K), P(hD|K), and P(hC|K), we need to take account of the observation selection effects through which our evidence about the world has been filtered.
How should we model these observation selection effects? Suppose that you are an angel. So far nothing physical exists, but six days ago God told you that he was going away for a week to create a cosmos. He might create either a single universe or a multiverse, and let’s say your prior probabilities for these two hypotheses are about 50%. Now a messenger arrives and informs you that God’s work is completed. The messenger tells you that universe exists but does not say whether there are other universes in addition. Should you think that God created a multiverse or only ? To answer this, we need to know something more about the situation. Consider two possible stories of what happened:
Case 1. The messenger decided to travel to realm of physical existence and look at the universe or one of the universes that God had created. This universe was , and this is what he reports to you.
Directory: preprints preprints -> Digitally-assisted discovery and proof preprints -> Reorienting the Logic of Abduction preprints -> Supplementary Material Table 1 Download 9.31 Mb. Share with your friends:
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