description

Poisoning the well is a type of ad hominem attack, intended to neutralize an opponent's arguments by rendering the audience hostile due to some personal feature, possibly related to the issue at hand. It is commonly an exposure of perceived bias.

Poisoning the well is more subtle than abusive ad hominem, in that it is contextual. Certain audiences will not be as affected by the comment. For example, it would not be effective to undermine a priest's argument in a church merely by pointing out that he's a priest. Poisoning the well is an attempt to use the audience's prejudices against the opponent. It is also somewhat different than argument from circumstantial ad hominem in that the dismissal is typically suggested in advance of the opponent's argument being heard. A sort of pre-emptive strike.

Often, there is some innuendo about conflict of interest, ulterior motive, or the inability to understand the complexities of the argument.

examples

"When you listen to my opponent's arguments against affirmative action, remember that he's white."

"When you listen to my opponent's arguments in favour of affirmative action, remember that she's black."