The other day, I nearly killed someone who was being too nice to me.

I was driving. I was taking a left-hand turn; my right of way. Suddenly, I noticed someone crossing the street right in front of me.

I slammed on my breaks and stopped short just a few feet in front of him. A moment passed where nothing happened and we just stared at each other in shock.

That's when it started. He began to gesticulate wildly, trying to wave me around him through the intersection, wearing this kind, friendly expression on his face that said, "Go ahead! I'll let you through!" He was smiling — he thought he was doing me a favor.

Given another situation, I might have taken him up on his offer. However, in this one, he was standing in the middle of the street. Oncoming traffic was headed toward him. I was safe in my car, but he was vulnerable on his feet. Yet, there he stood, aware of the danger, yet, ever so nicely offering to give up his pedestrian right of way so I could pass. I tried to shoo him away, like "Get out of the street!" but there he stayed, remaining in the road until traffic thankfully slowed down so we could end our awkward little song and dance safely. I drove away confused. Why had this person just risked his life to prove his own politeness? Did he think "Kill them with kindness" actually meant "kill yourself?"

Many of you probably think he was just being nice — after all, it ended happily, mercifully free of flattened pedestrians and screeching tires.

I disagree. I think he was being insipid. To me, and a growing number of researchers studying politeness and social interaction, he was demonstrating an example of "overcourtesy," an increasingly visible social epidemic in which acts of extreme politeness often end up harming the person who does them more than they help the people they're directed towards.

My run-in with the intersection guy is a perfect example. This man literally stood in front of oncoming traffic so he could demonstrate courtesy. Thing is, he didn't help me or himself by doing that. He put both of us in a dangerous situation.

Some other examples of overcourtesy that I, and probably you, have witnessed:

1. A person holds the door open for someone, but then gets stuck playing doorman for what seems like hours as a steady steam of thankless people see their courteous gesture and file through.

2. When a stranger sneezes across the room and someone shouts "BLESS YOU!" at them as if their over-polite exclamation were the one thing standing between them and years of cursed spiritual damnation.

3. When someone cuts you in line and you get so angry that your vision fades to white, but you just stand there indignantly, imagining what it would feel like to drop kick them, waiting in silence for the person to turn around and realize what they've done.

4. When someone passes you on the street and says "Sorry!" for no apparent reason, even though you were multiple feet away from each other and in no danger of colliding or even having to interact.

5. When you're late for a meeting because you've succumbed to clipboard-laden non-profit volunteers outside the grocery store who just want $54 of your money each month to save an endangered seal pod in Ecuador.

These are all nice things, sure. But, they're problematic for the people that do them. They signal a dangerous social need to put other's safety, well-being, time and priorities before our own, which, as author Adam Khan puts it, "benefits nobody."

In his book Principles for Personal Growth, he writes: "There such a thing as 'too much of a good thing.' Courtesy and kindness can be overlearned — to the point where the person doesn’t even know what he [or she] wants any more — where he’ll stand there and listen to the worthless ramblings of an idiot who just likes to talk, without the guts to be 'rude' and excuse himself because he’s got better things to do. Someone who has overlearned politeness will be too easily persuaded that such-and-such is right and good, only to figure out later that it’s not right and good for him."

Here's the problem with that.

Being too polite is a sign that you don't know what you want. When you allow courtesy to dominate your self-awareness, you also allow other people's needs to dominate yours.

For example, take James, a regular at the same coffee shop I haunt. He tells me he wishes he "had the balls to end a boring conversation" (hopefully not in reference to the one we're having). "I have shit to do. My time is too valuable to listen to some people blab on about themselves. But there's that weird social thing where even though you're dying to get out of a conversation, you stay put and interact because it's painfully rude to cut them off and leave. There's been so many times I missed calls from my family, was late, or accidentally ignored someone I cared about just because I was paralyzed by seeming polite."

Same. I've been there. We all have. Yet, we allow ourselves be hit on by people we're not attracted to, be verbally drowned by whoever's sitting next to us on the plane, and to waste hours of time playing emotional sponge for friends who talk about the same problem over, and over, but refuses to solve it. We don't speak up when someone pronounces our name wrong. We eat the food the waiter brought us, even though it's not what we ordered. We don't voice our opinions, for fear of hurting someone's feelings. We stay silent about things that need to be voiced to the point that we can't hear them at all.

"If you’ve been trained from early on to suppress your own wishes, you may suppress them right out of existence," Khan warns.

This can have huge implications for women, who are often socialized to be courteous and accommodating at all costs, even when they're uncomfortable. That's why often, women are afraid to say no.

"As young children, girls are socialized to be nice and to be more in touch with their own and other people’s feelings than are boys," writes Kathryn J. Lively, P.h.D. in a Psychology Today article about why women sometimes have such a hard time saying 'no.' "There’s nothing wrong with being nice. And there is definitely nothing wrong with being liked. Boys on the other hand are socialized to be less attuned to people’s feelings, and to win. What this means is that when girls and boys and women and men start playing together, women are at a slight disadvantage. They want to play nice, whereas guys just want to win."

You've all seem examples of this happen, no doubt.

"I always feel obligated to give my number out to guys who ask for it, even though I'll never text them back" my friend Anna tells me during a conversation about whether other people see overcourtesy as a problem in the same way I do, or if I'm just an asshole. "It's easier to be polite than to outright reject somebody."

These ingrained beliefs carry over in to other areas of life as well. Because of that socialization, women are less likely to try to negotiate higher salaries at work.

What's lacking here — not just for women or the Prince of the Intersection — is a healthy level of selfishness. Some adaptive assholery, if you will. A bit of "me first" means you know what you want and need and how to voice it; that you value yourself enough to prioritize those needs over those of others.

No one's saying you need to take this to an extreme level; i.e. hurting someone else or gravely inconveniencing them just so you can go about your day in a way that best suits you. That's ridiculous and dangerous. It more applies to common, low-stake social situations like driving, holding the door open, interacting in conversation, negotiating and, most importantly, learning to say no.

If you need help asserting yourself in this area, or with feeling more validated in your newfound, beneficial selfishness, Khan has some tips for you.

"Start small," he writes. "In little situations every day, make small goals. Ask yourself 'What do I want here?' or 'What do I think would be the best thing to happen in this situation?' And then try to make it happen. Sometimes you’ll feel like you’re being rude. Sometimes the other person will think you’re rude. If, like you, the other person has also been overtrained in courtesy and undertrained in healthy selfishness, they'll take up your agenda and help make it happen, or at least, they won’t oppose you. One way or the other, you need to know what you want and you must be willing to speak up about it."

All this is a far cry from something seemingly insignificant like holding the door open for someone for too long, or letting someone else get away with sitting in your assigned seat. But, if you don't take those little, easy opportunities to speak up, you won't get the practice you need to do the same when you have something more important to address.

Be a bit of a dick every now and then. You might be surprised at how many less Ecuadorian seal pods you have to sponsor.