 How to account for selection effects, within a particular approach to confirmation theory, is one central issue in discussions of anthropic reasoning. This question is intertwined with other issues that are more muddled and contentious. Debates among cosmologists regarding “anthropic principles” ignited in the 70s, prompted by the suggestion that finely-tuned features of the universe—such as the universe’s isotropy (Collins &amp; Hawking 1973)—can be explained as necessary conditions for the existence of observers.[41] More recently, a number of cosmologists have argued that cosmological theories should be evaluated based on predictions for what a “typical” observer should expect to see. These ideas have dovetailed with work in formal epistemology. A number of philosophers have developed extensions of Bayesianism to account for “self-locating” evidence, for example.[42] This kind of evidence includes indexical information characterizing an agent’s beliefs about their identity and location. At present work in this area has not reached a consensus, and we will present a brief overview of some of the considerations that have motivated different positions in these debates.