Definition:Argumentum ad Hominem

Definition
An argumentum ad hominem is a logical argument that concludes the falsehood of a statement because it is made by a particular person or group of people.

It is reasonable to be suspicious of an argument if most of the assertions made by said person or group regarding the topic under discussion are false.

Otherwise, such reasoning is fallacious.

Examples
"I'm not even going to bother to read that proof you just posted up - if it's by you then it's bound to be rubbish."

"National Inquirer? Don't believe everything you read in there, those reporters are all crackpots."

Also known as
This is also called an argument against the person.

Also see

 * Argumentum Ad Baculum
 * Argumentum Ad Populum
 * Bozo Bit