So, Lone Starr, now you see that evil will always triumph, because good is dumb.
A common recurring thread in fiction is the idea that the hero, for various reasons, will engage in stupid actions largely because it is the "heroic", sometimes idealistic thing to do. This index catalogues the tropes that manifest this phenomenon.
Contrast with
Good Is Not Dumb. This trope is
not to be confused with Dumb Is Good.
Tropes:
