In popular culture, robots or other theory-of-mind-impaired fictional characters have difficulties with metaphors or indirect speech because they lack "common sense". In fact, common sense plays an even more central role in language processing than these depictions suggest. Compare:

(1) The city council denied the protesters a permit because they feared violence.

(2) The city council denied the protesters a permit because they advocated violence.

Most people interpret they as referring to the city council in (1) and the protesters in (2). It is hard to explain this without invoking common sense. Similarly, compare:

(3) The hat fit in the box because it was big.

(4) The hat didn't fit in the box because it was big.

Such examples are ubiquitous in natural language. In this talk, I will describe recent computational and experimental work that tries to make sense of this commonplace phenomenon.