gaslight

to manipulate someone psychologically so that they begin to question their own perceptions and memories

A denial here, a lie there, snide comments about our oversensitivity … these are the tools of an individual with the cunning knack of convincing us that we are the ones who are consistently in the wrong, that we're being ridiculous, and maybe even verging on the delusional. If you've ever been on the receiving end of this form of slippery, psychological ('/dictionary/british/underhand')">underhandedness, then you might be interested to know that there's a term for what you've experienced – this is what's known as being gaslighted.

If you gaslight someone, then essentially you make them doubt their reality.

If you gaslight someone, then essentially you make them doubt their reality. Drip by drip, you get them to question whether their perceptions are correct, and done slowly enough, your victim doesn't even realize that they're being conned. It's a surprisingly effective tactic for gaining control over someone. Perpetrators, or gaslighters, use a variety of techniques – denying that they said or did things, telling blatant lies, ('/dictionary/british/deconstruct')">deconstructing their victim's personality, aligning other people against them ('this person agrees that you're being stupid …'), the list goes on. But perhaps the most insidious of all is a refusal to acknowledge what their victim has actually experienced and knows to be true, an insistence that their (the gaslighter's) reality is reality. Tearing up someone else's reality in this way (especially if it's done by someone in a position of authority) can persuade an unsuspecting, perfectly rational person that they're unstable, and possibly even 'going mad'.

Of course that's the extreme end of gaslighting, but to give a more low-key illustration of the concept – imagine that Person A is someone who is, for real, consistently late, but when challenged by Person B about their behaviour, insists that B is being oversensitive and 'has a problem with time'. Person B possibly then ends up doubting himself, i.e. 'Maybe Person A is right, maybe I'm not flexible enough. Am I being unreasonable? Perhaps this is my issue, rather than Person A's?' You get the picture. This is a simple example of a phenomenon psychologists sometimes describe as the gaslight effect.

Gaslighting has emerged, somewhat disturbingly, as a rather topical concept in political commentary. US President Donald Trump has been accused of employing the technique in a variety of ways, such as doing particular things and later denying them, dismissing the concerns of others as oversensitivity, and claiming that outrageous statements are just jokes or misunderstandings.

Whether you subscribe to this view of contemporary 'reality' or not, there's no reason to doubt that the verb gaslight is making its mark on the English lexicon.

Background – gaslight

The verb gaslight is an interesting example of a compound word that has no semantic, or even metaphorical, correspondence with the concept it represents. It's in fact named after the 1944 film Gaslight (starring Ingrid Bergman and based on an earlier stage play), in which a husband slowly convinces his wife she is going mad by claiming that she is just imagining that the house lights are flickering, when in fact he is turning on lights in the attic, thereby reducing the gas flow to the rest of the house and causing the quite real flickering of the downstairs lights.