We are notoriously bad at assessing risk. One problem is that we confuse ‘scary’ with ‘dangerous.’ Many scary things are not in fact very dangerous. Airplane flights are a good example of this. Many dangerous things, on the other hand, fail to scare us—think French fries and global warming.
Moreover, in weighing competing scenarios and the threat they embody, our brain is wired to privilege certain calculations over others. As Tversky and Kahneman(link is external) have shown in their Nobel Prize winning research, humans think in heuristics—mental short cuts—that, while often useful, contain built-in blind spots that may lead us astray.