The Simulation Hypothesis undercuts the SIA/Great Filter Doomsday Argument

Abstract

The absence of evidence for extraterrestrial life suggests the existence of a Great Filter, a set of factors that in combination drive the probability of a given star producing expansionist interstellar civilization very low. * The self-indication assumption (SIA) says that you should think it more probable that you exist in worlds where there are more observers faced with your exact observations. * Several SIA Doomsday Arguments note that there can be more naturally developed observers on primitive planets if the Great Filter lies after us, e.g. civilizations like ours are incapable of space travel, self-destruct, or are suppressed by hidden aliens; thus such arguments claim SIA gives overwhelming reason to expect a civilization like ours to fail to expand. * However, these so-called SIA Doomsday Arguments don’t take into account the possibility of mature civilizations simulating previous ones. * SIA overwhelmingly favors the hypothesis of simulations because it allows far more observers in our apparent position. * The number of such simulations is maximized when colonization is frequent enough for a large share of all resources to be colonized, but is largely indifferent about precise frequencies given that; so SIA does not suggest that unsimulated civilizations that look like Earth face a late Great Filter. Note that we are not endorsing the underlying SIA decision making framework here, only discussing whether certain conclusions follow it. In dealing with such anthropic problems we would prefer approaches closer to Armstrong’s Anthropic decision theory, which we think is better for avoiding certain sorts of self-destructive anthropic confusions.