In 1964, campus Free Speech Movement activist Jack Weinberg coined the phrase "Don't trust anyone over 30" during a combative interview with a newspaper reporter. This was during a time when America was rebelling from the conservative 1950s 'I Like Ike' era, to being well into the liberal 60s and 70s.

I decided to tweak this a bit after a discussion with a group of people over 30, about how folks in their teens and twenties refuse to listen to the wisdom often found in older people.

I'm being cheeky of course with the brash title, but my intentions are honest. They can't be taught anything because many of them refuse to listen and learn. They think they know everything, when they actually know nothing at all.

So read on.

I was in an area with someone NLIHT (No Longer In His Teens) who was working on a project that was important to him. Turning around, I noticed that he had missed an important step that would end up being laborious to correct later.

At this point in my life I've learned to gauge whether someone is receptive to information before I download to them. I offered my take on what was up and how he could improve it, but my attempts at help were batted away.

"I'm an adult. I know what I'm doing."

No, you're an insufferable 21-year-old who's about to make an expensive mistake and you don't even know it.

If there's anything you should learn about people it's that you should:

Never Trust Anyone Under 30.

People in their teens and twenties are the most know-it-all types, and the most resistant to information from others who have been where they are now. While technically adults, they lack the all-important life experience that the generations before them have.

Part of it is that they're fresh out of their teens and don't want to be treated as a child anymore.

I get it.

I remember when I turned 20 (but still looked as if I were 16 or so). I HATED people referring to me as a boy, because, after all, I was an adult, right?

However, the difference between me and my peers, is that I eagerly sought out older people who had the knowledge and experience that I lacked.

I would pepper them with questions again and again. I wanted to know the "why" behind everything, and had an insatiable thirst for knowledge, and they were only too happy to oblige a young man who was actually willing to listen to them.

That's not to say that they always made the correct decisions in life, but I realized that I could learn as much (if not more) from their failures, than I could from their successes. A lot of the perceived "wisdom" you hear from me come from my inquires of older people, and my willingness to shut up and listen.

Learning from those who have been there

Take drinking.

I don't drink, and don't understand the attraction to it. At least I didn't have much of a handle on it until I decided to sit down with some alcoholics in my neighborhood when I was 17.

I was that kind of 17-year-old who they said was "wise beyond my years" but it was simply due to my unquenchable thirst for information. Beer and hard liquor absolutely REEK to me. It's like smelling rubbing alcohol and ten deciding to quaff down the entire bottle.

But the drunks explained that it was an ACQUIRED taste, something that was developed over time. Much like yogurt, which I hated until a Russian-American woman gave me a sample of freshly-made yogurt as opposed to the cheap slop sold then in many American supermarkets.

I was fascinated to learn from her about the health benefits and the positive effects on gut health that GOOD yogurt provides. She also taught me something that I and I'm sure many other people didn't know about just how an important a part that our gut microbiome plays in our immune system. Thanks to that amazing Russian woman, I've eaten yogurt ever since, and I never get sick.

The year I met her (at 16), was the last year I ever got the flu. I used to get it every year like everyone else, but I haven't had it since then...

Manager? Supervisor? I don't think so...(Way too Childish and Immature)

People in their teens and twenties often make HORRIBLE leaders. These "managers" often have never had any supervisory experience, and simply just want to throw their weight around. I'll never forget the guys who were between 19 and 22 and were talking to a 20-year-old who'd been a "manager" at a fast food joint for six month.

You should've heard them.

One was up for the next "leadership" position and was about to enter "manager" training. He asked the guy what it felt like to fire somebody, saying: "I can't wait to get my power and fire my first person."

So as the nut-job started to explain how macho he felt when he engineered his first termination, I jumped in saying "actually, you don't want to fire anyone unless it's absolutely necessary. It deprives you of an experienced worker, leaving you short-handed until the new hire is trained-up and gains experience.

That wasn't the answer they wanted to hear from someone who had actual experience managing people.

After I left that place, there was a wave of engineered terminations by these kids who finally got to shoot their load and fire people. They ended up pushing out some of the best people there just so they could flex. And by the time senior management stepped in and terminated them, the damage was done.

You need someone with life experience in order to build the foundation to be a great manager. I prefer elevating people who've made mistakes and more importantly, LEARNED FROM THEM.

You also don't EVER want to promote someone as a supervisor who's lobbying for the position.

I've found that the best leaders are those quiet people who show up every day and just do their job. They're responsible, and are the backbone of your organization. The fact that they're not looking to be a manager, shines the light on exactly why they should be one.

Accidents will Happen

Cocksure people in their teens and twenties can get you badly hurt or even killed. At those ages you think you're invincible, and since you're now an "adult" you're also a know-it-all.

We were driving to work in a company van with a 22-year-old from NYC. He didn't know the area, and I'd reminded him early on to slow down ahead of a well-known dangerous bind curve.

It's one of those areas where the road curves around a steep hill hiding a line of cars at a red light. If you live in this part of the state you know about that 'Deadman's Curve' but he was from NY, and didn't.

So I see it coming up, and I warn him to slow down. He yells back "I know what I'm doing!" and Mr. 22-year-old is full speed ahead. So I yell "brace yourself!" as he's approaching the danger zone at high speed.

Sure enough, there's a long line of cars stuck at a red light, that couldn't be seen due to being hidden by the hill. Realizing his error, and seeing that he's about to plow into the vehicle in front of us, I yell "the shoulder!" and at the last moment, he turns onto the left shoulder of the road clipping cars on our right.

It was an expensive lesson for him.

This is just one example of many concerning people who refuse to heed good advice due to youth and inexperience.

30s, The Age of Awareness

Talk to almost anyone you know who've crossed that threshold at 30. Many people don't even begin to get serious about life until they hit that number. Looking back at their teens and twenties when they partied all night then passed-out drunk until they next day.

I had a friend who got blackout drunk and woke up totally nude in bed with another man with no memory of what happened between them and who the fuck undressed him (and what in the hell did they do to him AFTER he was undressed!).

By 30, you either have your first kids are are about to. You're getting tired of the one night stands and are getting ready to settle down with one man, woman, lady-boy, or whatever floats your boat.

You're no longer thinking I-want-to-party-all-night-until-dawn-then-puke-my-guts-out-and-go-to-sleep.

Because now you have wisdom that can only come after years of making mistakes. Now you're really an adult.