Ad Hominem

An ad hominem fallacy happens when someone attacks the person making the argument instead of addressing the argument itself.

The truth or falsehood of a claim isn't determined by who says it. A person can have bad motives, an unpleasant personality, or even be wrong about many other things and still make a valid argument. Likewise, a kind, intelligent, or respected person can still make a bad argument.

When someone resorts to attacking the person rather than answering the argument, they've shifted the discussion away from the issue at hand.

Example

Christian:

"I believe the historical evidence supports the resurrection of Jesus."

Atheist:

"Of course you believe that. You've been brainwashed since you were a kid."

Notice what happened.

The atheist never addressed the historical evidence. Instead, they attacked the Christian's upbringing.

Even if the Christian had been brainwashed, that still wouldn't tell us whether the resurrection actually happened. The argument still stands or falls on the evidence, not on the person presenting it.

This works both ways.

Christian:

"You only reject God because you want to live in sin."

Maybe that's true of some people. Maybe it isn't. Either way, it doesn't answer the atheist's argument. Attacking someone's motives doesn't prove them wrong.

That is an ad hominem.

How to Respond

Don't get pulled into defending yourself. Bring the conversation back to the argument.

You could say something like:

"Whether I'm brainwashed or not has nothing to do with whether my argument is true. Let's look at the evidence."

Or if someone questions your motives:

"My motives don't determine whether my conclusion is correct. Let's focus on the argument itself."

A good discussion examines ideas, not personalities.

Practice

The next time you're reading comments online, ask yourself:

"Did they respond to the argument, or did they attack the person making it?"

Once you start looking for ad hominem attacks, you'll realize how common they are. They're often used because attacking a person is much easier than answering a difficult argument.