And yet, on questions such as this – as with so many important political, social, economic, and cultural issues – what we come to believe is not based on the facts alone, if at all. Sometimes we may indeed think deeply about the pros and cons of each argument, actively seeking information and data that would support one view over another; in other cases, however, we rely on a “quick and dirty” evaluation of the arguments, focusing not on evidence, but rather on an advocate’s expertise or popularity.