3. Logical Fallacies: Equivocation

Second is the fallacy of equivocation, also known as debate and switch. When debating any topic, it's important that we pay close attention to the meaning of words and how they're being used in the debate.

Most words have more than one meaning, but only one of those meanings will properly fit the given context.

When someone shifts from one meaning of a word to another within an argument, he or she has committed the fallacy of equivocation.

Here's a facetious example. Doctors know a lot about medicine, and Dr. Lyle is a doctor, so he must know a lot about medicine, right?

So anybody with a PhD is considered a doctor, but that doesn't mean they're a medical doctor. So what the person is doing is taking the word doctor and meaning it in one sense at the beginning of the argument and in another sense at the end of the argument, or conflating it.

The short argument shifts from one meaning of the word doctor, medical doctor, to another meaning, PhD. So this would be another example.

I know evolution is true because we see evolution happening all the time. So what word are they using in there and have two different meanings with?

Someone? Evolution, right? We know evolution is true, and what they mean by evolution is macroevolution, large -scale changes over time, because we see evolution happening all the time.

The second evolution is microevolution. Yeah, we see changes, we see adaptation, but we never see something going from one species to another species.

So they take macroevolution and say it's true because we can see microevolution. That's a big jump.

They're using that word with two different ways. So that's the fallacy of equivocation.