On this week's Rule Breaker Investing podcast, Motley Fool co-founder David Gardner takes a break from his usual topics and generally upbeat outlook to dig into some things that just irk him. He thinks we'd all be better off retiring some phrases from our vocabularies, because they're linked to ideas we'd do well to dump as well.

In this segment, he addresses a pair of things that get him steamed: First is when he -- or anyone -- is called out for being "defensive" and he's going preemptively on the offense to explain why. Then, he jumps to our ideas about class in America. Ask a person making $24,000 a year and one earning $240,000 what class they're in, and both will likely give the same answer. What David wonders is: Can we stop pretending we're all middle class, and start addressing the poor and the rich, too?

A full transcript follows the video.

This video was recorded on Nov. 15, 2017.

David Gardner: Pet Peeve No. 3: I'm assuming this has happened to you dozens of times. It certainly has to me. And the first couple of dozen I kind of accepted at face value and tried to react to it. And then the next dozen or so it happened. I started questioning it and now I've come down in a new place. It's when somebody, usually in an argument, tells you, in some form, "Quit being defensive. You're being defensive. Quit being defensive."

Now what's hilarious about that line, to me, is that that is an attack itself. That is an assertion. That is immediately going on the offense whenever you call somebody out as defensive. In fact, probably the person who's saying, "quit being defensive" is the more defensive of the two people.

And as I've thought more about this, I think the best way that you or I can react [whenever we're accused of being defensive by somebody who is pursuing an offensive strategy] is say something like, "You're darn right I'm being defensive. If I were attacking you like you're attacking me, wouldn't you get defensive?"

I would suggest a higher ground is never to call somebody defensive in any context, especially in arguments because (a) if they are anyway, that doesn't help and (b) it's kind of hypocritical to put somebody rocking back on their heels by calling them defensive and put them in a catch-22 situation. Admittedly it might be a good strategy in a debate, but I don't think it's a great way to win arguments in real life. Enough with the whole being defensive thing.

Pet Peeve No. 4: Pet peeve No. 4. Now this one gets in a little bit thorny territory for some people, maybe especially Americans, because we like to think of ourselves, often, and I think it's part of our heritage, as kind of a classless society. After all, a lot of us fled other societies, especially Old World societies, where things were very stratified and regimented.

And part of the truth of the American dream, it's just as true today, is that you can come from nothing and really be running everything. And that's often very clear to investors, people like you and me, who see amazing people come from nothing and end up creating some of the great companies of our time. It's always going to be true. Think about Steve Jobs and look at his background if you're ever skeptical. I love that about our country.

But what I don't love is when we get into some of the class talk. Briefly I'm going to share, and probably through some foreign eyes, because sometimes the best way to see ourselves is to look through someone else's eyes who's not in your own country.

I was having a conversation with an Australian Fool last summer and I was saying, "I don't like it when people invoke the phrase "middle class" because often, if it's in public conversations, it's going to be making a political point. We're going to be talking about the middle class."

And the funny thing I said to this Australian Fool friend of mine is that I would love to see that actually defined. As much as we talk about the middle class, who is in the middle class? And one of the first things you can do is just ask somebody to define what they consider to be the middle class. "How do I know? What are the numerical parameters? How are we having this conversation right now? I realize whatever point you're making might be a political point, but who exactly are you talking about?"

So I said that to my Aussie friend and he said, "It's actually interesting." And I won't attempt my bad Aussie accent here. But my friend Claude, said, "You know what's really interesting? As much as we hear you all talk" -- this is more kind of last year, election time -- "as much as we hear you all talk about the middle class, if you're going to have a middle class, and talk about a middle class, you should also be talking about the other classes, too."

And Claude said, "I never really hear you talking about the lower class. I don't really hear much talk about the upper class. And if you're going to talk about the middle class so much in your country, you probably should acknowledge the existence of others and talk about them, too. They also matter."

I thought that was a pretty good point addressing one of my pet peeves, and maybe that speaks to you, as well. Thanks, Claude.

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