Best-selling author Dan Harris says this is the biggest problem people have when they start meditating

According to Nightline anchor and bestselling author Dan Harris, everybody learns an incredibly important lesson the first time they sit down to meditate.

"That your mind is out of control," he says.

Harris speaks from experience.

He's been sitting for about six years. He traced his path to the cushion in the bestselling memoir "10% Happier: How I Tamed the Voice in My Head, Reduced Stress Without Losing My Edge, and Found Self-Help That Actually Works--A True Story."

He now gives multiple talks a week about mindfulness around the country.

His audiences are excited about the practice, he says, but they'll often tell him that it's not for them.

"The pushback that I hear from people is, 'Yeah, I get it, it's good for you and I should do it, but I can't because my mind is too busy," he says.

He calls it the fallacy of uniqueness: my mind is too busy to meditate, so I shouldn't bother to try it.

"The good news and the bad news is you're not special," he says. "Welcome to the human condition, all of our minds are like this."

It's a subtle - but profound - misunderstanding.

"It really does display a shocking ignorance about the internal weather of everybody else on the planet with whom they coexist," he says. "Do they imagine that everybody else's internal dialogue is all rainbows and unicorns? It's a strange belief to hold, if examined."

This, Harris says, is part of meditation's PR problem. In addition to still having the association with new age weirdos and self help gurus, there's a popular conception that the point of meditation is to have a clear mind, preferably while you wear white robes and peer over a serene landscape.

The real process of meditation is much more mucky than that.

"The best way to deal with the PR issue around people thinking they can't meditate is just to point out that you don't have to clear the mind, that's not possible unless you're like an incredibly high-level meditator," Harris says. "The point is just to focus the mind for a few nanoseconds at a time, get lost and start over, and then get lost and start over, ad infinitum."

In other words, the "point" of meditation isn't to get rid of your mental clutter - but to get really, really familiar with it. Then, over time, be able to let it go.

"The way to think about it is like physical exercise," Harris says. "You know if you go to the gym and it's easy, you're probably cheating. And if you meditate and it's easy, you're either enlightened or you're dead."