susceptibility

This susceptibility to impressions had been his undoing, no doubt. Still at his age he had, like a boy or a girl even, these alternations of mood; good days, bad days, for no reason whatever, happiness from a pretty face, downright misery at the sight of a frump.

A man who lacks understanding is susceptible to deception

We don't do well with infinity and endless possibility, and so we break things down into individual units and into stories. And then we accidentally believe in those stories, and we accidentally start acting them out. Stories about what love is, what happiness is. What men are, what women are. Unable to shape our own stories about the madness that surrounds us, we get infected with other people's stories, trying to ignore the discomfort that comes with an imperfect fit.