Appeal to Pity
Explanation
An appeal to pity attempts to persuade using emotion--specifically, sympathy--rather than evidence. Playing on the pity that someone feels for an individual or group can certainly affect what that person thinks about the group; this is a highly effective, and so quite common, fallacy.
This type of argument is fallacious because our emotional responses are not always a good guide to truth; emotions can cloud, rather than clarify, issues. We should base our beliefs upon reason, rather than on emotion, if we want our beliefs to be true.
Examples
Pro-life campaigners have recently adopted a strategy that capitalises on the strength of appeals to pity. By showing images of aborted foetuses, anti-abortion materials seek to disgust people, and so turn them against the practice of abortion.
A BBC News article, Jurors shown graphic 9/11 images, gives another clear example of an appeal to pity:
“A US jury has been shown graphic images of people burned to death in the 11 September 2001 attack on the Pentagon. The jurors will decide whether al-Qaeda plotter Zacarias Moussaoui should be executed or jailed for life... Prosecutors hope such emotional evidence will persuade the jury to opt for the death penalty.”