moving the goalposts

/ˌmuːvɪŋ ðə ˈɡoʊlpoʊsts/

changing the criteria for proof after evidence is presented

moving the goalposts in a sentence

“After she met his demands, he moved the goalposts.”

English moving from Old English movan + goal from Middle English gol boundary + post from Latin postis pillar

Related Words

no true Scotsman

dismissing counterexamples by redefining the group

red herring

introducing an irrelevant topic to divert attention

slippery slope

arguing that one event will inevitably lead to extreme consequences

straw man

misrepresenting someone's argument to make it easier to attack

sunk cost fallacy

continuing something because of previously invested resources

tu quoque

deflecting criticism by pointing to the critic's similar behavior