Fallacies of relevance occur when the premises are logically irrelevant to the conclusion, even if they seem psychologically persuasive.
Ad Hominem (Against the Person)
Attacking the character or circumstances of the arguer instead of the argument itself.
Example: "You shouldn't listen to his economic plan; he's never had a real job."
Straw Man
Distorting an opponent's argument to make it easier to attack, then knocking down the distorted version.
Example: "Those who want to cut defense spending clearly want to leave us defenseless against attack."
Red Herring
Diverting attention by changing the subject to a different but subtly related one.
Example: "We should not worry about climate change because we need to focus on the economy."
Appeal to Authority (False Authority)
Citing a witness or authority who is not trustworthy or is not an expert in the relevant field.
Example: "This celebrity says this diet is the best, so it must be true."