At its heart was the idea that stupidity was not mere ‘dumbness’, not a brute lack of processing power. Dumbness, for Musil, was ‘straightforward’, indeed almost ‘honourable’. Stupidity was something very different and much more dangerous: dangerous precisely because some of the smartest people, the least dumb, were often the most stupid.
What exactly is stupidity? How does it relate to morality: can you be morally good and stupid, for example?
Stupidity is rather one specific and stubborn cause of error.