From the wiki article describing the play/movie the phrase comes from:
“In the story, the husband secretly dims and brightens the indoor gas-powered lighting but insists his wife is imagining it, making her think she is going insane.”
Imo it’s when someone is deceived by a person who lies about the actual state of affairs/reality to make the other person question what they experienced as credible. I don’t think that’s the same as when someone helps question beliefs in general because skepticism is good to make sure we aren’t self deluding, but if that person is lying about reality to manipulate them it becomes bad/gaslighting.
Another example I think is from it’s always sunny in Philadelphia in the episode where Dennis and Mac go to live in the suburbs and Mac asks Dennis if he hears a beeping the audience can hear and Dennis says he can’t until he blows up saying of course he can when berating Mac. Dennis is angry at Mac and in retaliation he gaslights him about the annoying beeping sound to manipulate him into questioning if the beeping is real or an audio hallucination.
spookex@lemmy.world 7 months ago
I’m going to try to explain the origins from memory so someone who knows more will probably explain better.
It comes from an book or a movie, where a husband is planning something nefarious (don’t remember if it’s a murder or something) and he uses the attic of his house to do it. This is set back in the days when they used gas for lighting things and when he turns on the lighting in the attic, it causes the lights to change (probably get dimmer) in the rest of the house. His wife notices this and brings it up to him, since he obviously doesn’t want to reveal that he is the one causing it, he constantly convinces his wife that it’s all in her head and that she might be losing her mind.