Poisoning the well is an ad hominem attack (see “Ad hominem,” above) on a person’s integrity or intelligence that takes place before the merits of a case can be considered. On the other hand, An ad hominem (Latin for to the man or to the person), short for argumentum ad hominem, is an attack on an argument made by attacking the character, motive, or other attribute of the person making the argument, rather than attacking the argument directly.
Poisoning the Well Fallacy. Poisoning the well is an ad hominem attack (see “Ad hominem,” above) on a person’s integrity or intelligence that takes place before the merits of a case can be considered. It redirects a discussion to the faults of one of the parties. Poisoning the well can be a special case of argumentum ad hominem, and the term was first used with this sense by John Henry Newman in his work Apologia Pro Vita Sua (1864). An ad hominem (Latin for to the man or to the person), short for argumentum ad hominem, is an attack on an argument made by attacking the character, motive, or other attribute of the person making the argument, rather than attacking the argument directly. Mike. Poisoning the well is indeed a logical fallacy. It is a special case of the ad hominem logical fallacy in which an argument is framed in terms of a certain claim being wrong because of some negative attribute of the claimant. Poisoning the well is a preemptive attack on a person in order to discredit their testimony or argument in advance of their giving it. A person who thereby becomes unreceptive to the testimony reasons fallaciously and has become a victim of the poisoner. This is a kind of ad hominem, circumstantial fallacy. Abusive ad hominem usually involves attacking the traits of an opponent as a means to invalidate their arguments. Equating someone's character with the soundness of their argument is a logical fallacy. Ad hominem abuse is not to be confused with slander or libel, which employ falsehoods and are not necessarily leveled to undermine otherwise sound stands with character attacks. Ad hominem circumstantial constitutes an attack on the bias of a source. This is fallacious because a disposition to make a certain argument does not make the argument false; this overlaps with the genetic fallacy (an argument that a claim is incorrect due to its source).
http://www.butte.edu/departments/cas/tipsheets/thinking/fallacies.html https://en.wikipedia.org/wiki/Poisoning_the_well https://en.wikipedia.org/wiki/Ad_hominem http://theness.com/roguesgallery/index.php/logicphilosophy/poisoning-the-well/ http://www.iep.utm.edu/fallacy/ https://en.wikipedia.org/wiki/Ad_hominem https://en.wikipedia.org/wiki/Ad_hominem
What’s the difference between ad hominem fallacy and the poisoning the well fallacy?