Recent developments in cosmology indicate that every history having a non-zero probability is realized in infinitely many distinct regions of spacetime. Thus, it appears that the universe contains infinitely many civilizations exactly like our own, as well as infinitely many civilizations that differ from our own in any way permitted by physical laws. We explore the implications of this conclusion for ethical theory and for the doomsday argument. In the infinite universe, we find that the doomsday argument applies only to (...) effects which change the average lifetime of all civilizations, and not those which affect our civilization alone. 1. Introduction2. Physics background2.1The number of possible histories is finite2.2The universe is infinite2.3Every possible history occurs an infinite number of times3. Frequency and probability4. Inflation contrasted4.1Modal realism4.2Actualism4.3Eternal recurrence5. Ethical implications6. Universal doomsday6.1Application to our civilization in particular6.2Universal vs. particular dooms6.3Practical applications7. Concluding remarks. (shrink)

Austin's lecture on this topic contributes little to the problem of freedom of the will, and so in my discussion of his ideas I shall stop short of the difficult part of that problem. His most important positive suggestion is that hypotheticals should be divided into two classes, conditionals and pseudo-conditionals. He claims that neglect of this distinction has been the cause of mistakes in certain forms of the dispositional analysis of the statement that an agent could have acted otherwise, (...) and he then goes on to criticise all forms of that analysis using arguments which do not depend on the difference between the two kinds of hypothetical.This discussion will be in two parts. In the first I shall take up Austin's distinction between conditionals and pseudos and criticise it and develop it at length, because it seems to me to be the most important thing in his lecture. Since I shall not have space for comment on fortuitous errors made by defenders of the dispositional analysis of the claim that an agent could have acted otherwise, I shall concentrate on the essential features of that analysis. (shrink)