“Gaslighting” is suddenly in everyone’s vocabulary. It’s written about, talked about, tweeted about, even sung about it.

It’s become shorthand for being manipulated by someone who insists that up is down, hot is cold, dark is light—someone who isn’t just lying about such things, but trying to drive you crazy.

The term has its origins in a 1944 film in which a husband does exactly that to his wife, his crazy-making efforts symbolized by the rise and fall of the gaslights in their home. Kate Abramson examines gaslighting from a philosophical perspective, investigating it as a distinctive moral phenomenon.