poisoning the well
/ˈpɔɪzənɪŋ ðə ˌwel/
preemptively discrediting an opponent
poisoning the well in a sentence
“Before he speaks, remember he's been wrong before.”
Origin of poisoning the well
From literally poisoning a water source to harm those who drink from it
Related Words
tone policing
dismissing an argument based on how it's expressed
sealioning
persistently demanding evidence in bad faith
bandwagon
arguing something is true because many people believe it
appeal to popularity
citing popularity as evidence of truth
appeal to force
using threats instead of arguments
appeal to pity
using sympathy to substitute for evidence