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The Oxford Companion to Philosophy Part 21

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The Oxford Companion to Philosophy Part 21. The book is alphabetized by the whole headings of entries, as distinct from the first word of a heading. Hence, for example, abandonment comes before a priori and a posteriori. It is wise to look elsewhere if something seems to be missing. At the end of the book there is also a useful appendix on Logical Symbols as well as the appendices A Chronological Table of Philosophy and Maps of Philosophy. | 180 cosmology evidence suggests the universe looks roughly the same in all directions from any point of view then it must be either expanding or contracting. About the same time and using the same method the Doppler effect by which we can tell whether an ambulance is moving towards or away from us namely from the pitch of its siren Hubble verified that distant galaxies are receding from the earth. One might think Hubble s observation suggests that the focal point of the universe s expansion must be somewhere near the earth and therefore that the universe is not the same from any point ofview. But if the earth s location is like a point on a uniformly expanding sphere say an inflating balloon then from any other standpoint on the sphere one would have to observe the very same expansion. There are in fact three general relativistic scenarios compatible with Hubble s observation. The first extreme is that the universe started expanding so slowly that at a certain point in our future gravitational forces are going to take over and cause it to collapse back on itself. The second extreme is that the universe started out expanding so quickly that gravitational forces will never hold it back and it will go on expanding for ever. Finally there is a middle way the universe started off with just enough expansion to allow it to just escape eventual collapse. None of these scenarios has yet been totally ruled out though curiously something like the middle way looks to be the best candidate . But they all require that the universe began in a highly compressed big bang state following an initial singularity i.e. a point at which physical laws break down. All this has revived two old bones of contention whether the universe needs a creator and whether its unique features are evidence of design. To avoid the need for divine intervention at the big bang some physicists modified general relativity to produce a steady state model of the universe. In this model the universe has always