“Red Herring” is another well-known fallacy type, but it’s easily confused with “straw man”, so I here I want to highlight the differences between the two.
The name “red herring” comes from an old method of training dogs for fox hunting. The goal is to train the dogs to follow the fox’s scent, even if the dogs encounter other smells that are potentially distracting.
So what they do is they let the fox go, so the fox leaves a scent trail. Then, before letting the dogs go, they drag a bunch of smelly red herrings across the fox’s trail.
Then they release the dogs. When the dogs hit the herring trail they’ll be distracted by the smell and some will be inclined to follow the herring trail instead, so the trainers try to get the dogs to stay on the fox trail and resist the urge to follow the herring.
So, how should we interpret this metaphor?
Well, the fox is some argument, the original argument that is at issue in a debate.
The dog can represent anyone who is interested and engaged in this argument.
The red herring is something that distracts you from following the trail of the original argument. It might be a new and different argument that raises a different issue, or simply an irrelevant comment that distracts from the main issue. What’s important is that it’s distracting enough to make the audience want to follow this new trail, away from the original argument and the main issue.
So, putting all this together, you commit the red herring fallacy when, in an argument, you divert attention away from the main issue or the main line of argumentation by introducing something that changes the subject, that raises a new issue that isn’t relevant to the preceding line of discussion.
The fallacy really occurs when you then conclude something from this different issue, or presume that some conclusion has been established, and use this to claim that you’ve won the argument or said something relevant about the original argument.
In this respect the fallacy is very much like a straw man fallacy, in that you’re mistakenly or misleadingly saying that you’ve won an argument or refuted an argument when all that you’ve really done is avoid engaging the original argument.
But it’s different from the straw man in that a straw man involves distorting or misrepresenting some original argument, and then knocking down the distorted argument.
In a red herring, the arguer ignores the opponent’s argument, and subtly changes the subject. So, to distinguish between the two, you need to ask yourself whether the arguer has knocked down a distorted argument or simply changed the subject.
Here’s a summary of the points just made.
To illustrate the difference, consider this example:
“I overheard my friend John argue that the Bible has errors in it. Funny, I never figured him for an atheist.”
This is a straw man, not a red herring, since the conclusion being drawn is related to the main argument that his friend is making about the Bible, but it’s clearly working off of a distorted or exaggerated version of it if it equates biblical fallibilism with atheism.
Now compare that to this one:
“My opponent has argued that there’s an urgent need to reduce greenhouse gases in order to minimize global warming. But the most serious problem facing future generations is the risk posed by nuclear weapons in the hands of rogue states and terrorists. This is where we need to focus our attention and resources.”
This is a red herring. The original issue was about greenhouse gases and the urgency of global warming. This response side-steps that issue and introduces a new issue.
To avoid committing a red herring, the arguer would need to show that global warming isn’t an urgent problem, or that reducing greenhouse gas emissions won’t be effective in reducing it, or something like that. Nuclear weapons in the hands of terrorists is certainly a serious issue, but that fact does nothing to undermine the original argument about global warming.