The Dunning-Kruger effect is a mental bias where people with low skill or small knowledge in a specific area think they are much better than they actually are.

I had to go look for the clip because I hadn't seen it. He made the statement in a joking manner, but it's not entirely wrong. If he's a legit blue belt and all else is equal he could tear up someone else. He even acknowledged that he couldn't do it to someone larger than him. I've filed it in the who cares part of my brain.

To be fair. Most blue belts should be able to handle an untrained person though. People with zero training are absolute shit at fighting.

I thought that Jonah Hill was speaking hyperbolically so that he could make a joke. Also, as others have pointed out, a blue belt can generally handle most untrained people (unless they are much bigger or they have a weapon)… probably including Jason Bateman. On the plus side, Hill is an example of how BJJ can have a positive effect on someone’s life. He seems to be in much better shape and he has a lot more self-confidence as a result of his training. I will admit that that clip of him saying “I would f––– you up” and “I would f–––ing annihilate you” might make him look like a cocky bro-dude. However, it probably wouldn’t have been as funny for him to say, “I would calmly take you down and submit you without causing you serious injury” or “I would hang onto you in the guard until help arrived.” :)

I keep a distance from the Jiu-Jitsu community except when on the mats.

Their mouths and behaviors are often boorish at best, and shameful and/or embarrassing at worst.

Likewise, anyone that measures their self-esteem based on who they make tap or who made them tap is suffering from serious mental weakness.

A word of nuance, to my earlier statement, in light of those made since by others on other forum threads.

Those same players, who in peace time, or in health, are not appropriate, are sometimes ideally fit in combat, emergency, or in cancer beds, or intensive medical care or other emergency domains.

These same demons, that are present in every boxing ring when any human that enters brings them or does not enter,

Are awfully inconvenient in the wrong environments and domains, but can be quite useful in others.

So, what do I know, and what lies, do I tell?

The Truth is, it's complicated, and simple, and statistics are like meat pies, and rules of thumb and other heuristics have horrible histories but may be reforms in their time and application.

Even if they appear unexpected from the perspective of whatever goggles are in fashion at the moment, and time in place, and space.