Doomsday rings twice

This paper considers the argument according to which, because we should regard it as a priori very unlikely that we are among the most important people who will ever exist, we should increase our confidence that the human species will not persist beyond the current historical era, which seems to represent a crucial juncture in human history and perhaps even the history of life on earth. The argument is a descendant of the Carter-Leslie Doomsday Argument, but I show that it does not inherit the crucial flaw in its immediate ancestor. Nonetheless, we are not forced to follow the argument where it leads if we instead significantly decrease our confidence that we can affect the long run future of humanity.