1. We side with the underdog. 1A. Polling on Israel-Palestine shows a shift in support given to the side that appears to be the underdog. 1B. Despite being evil we sort of think bin Laden is cool for taking on the US by himself. 1C. When we tell stories we tend to identify with and root for the underdog, i.e. Leonidas.

When we want to know why (1.) I take it that any explanation that includes any of the sub-premises is question begging.

Psychohistorian's response was that (1) is caused by the fact that in our stories the underdog is always the side we identify with and root for and this leads us to assume that the underdog is the "good side" and therefore side with the underdog. But as I took the question (1) part of what needed explaining was underdog identification in stories.

This mess about what makes an "interesting story" was added after the initial comment and it confuses things. As I took the initial comment the only evidence being presented was the vast collection of pro-underdog stories and the dearth of pro-overdog stories and this was taken to be sufficient lead us to side with the underdog. I don't think this response is especially helpful because part of our reason for even thinking that there is an underdog bias is the fiction. Throwing in "interesting" adds another step to the argument and this version might not be begging the question anymore (though I'm not convinced of that either).