The 5 biggest life lessons this dad learned from his 4-year-old: 'Why can't most adults get this?'

On October 15, 2015, my wife and I welcomed our son into the world. The day after he was born, I wrote him a list of money advice.

But parenting has been a humbling experience, and four years later, I realized that he's taught me so much. Kids are fascinating; they're free from the social pressures and biases that cause adults to think in strange, unproductive ways.

Here are the top five life lessons I learned from my kid:

At age one, my son didn't talk. But he communicated more effectively that many executives I've encountered.

One-year-olds don't beat around the bush, either. If they want something, they tell you — loudly and immediately. If they're unhappy, they let you know. When they're done with something, they drop it and walk away.

Too many adult conversations drag out over weeks or months before one person says, "I wish you had just told me how you felt from the beginning."

Babies have no tolerance for that stuff, and their ability to get to the point saves countless hours of back-and-forth.

Happiness doesn't scale perfectly with wealth because people's expectations rise with their income. Something similar happens with age.

Our ability to be wowed by simple things peaks at around ages six to seven. One-year-olds, however, haven't seen much of the world, so their expectations are low — which means they spend a lot of their days having their minds blown in a state of pure bliss.

Turning on the ceiling fan, for instance, would bring my son a level of happiness that the average adult probably experiences once a year. How can you not envy that? Everything is amazing when you expect very little.

Anything can upset a child, but they recover and move on astonishingly fast. The time between my son's world coming to an end and the greatest moment of his life can be measured in seconds.

Grown-ups, on the other hand, dwell on situations for years, often for no other reason than their own insecurities needing something to do. One-year-olds hold no grudges. They forgive and forget.

The past is behind us. What truly matters is what's ahead of us. Why can't more adults get this?

Babies are learning machines. The cognitive progress they can make in a week is almost unbelievable. There's certainly a biological reason for this that I don't understand, but it's clearly helped by their ability to be curious about everything.

What does this do? What happens if I open this? Where does this door lead? What does that leaf feel like? They spend much of their day trying something they've never done before. Their life is a giant experiment.

Adults don't do this, because they have a preconceived idea of how things might turn out, so they tend to stick to what they know. Children aren't anchored to past experiences, so they're willing to try any combination of new ideas they can think of.

The result? A staggeringly fast mode of learning and discovery.

Kids can spend the whole day experimenting and trying something new because they're impervious to embarrassment.

They don't care if they look ridiculous. They don't mind if you're judging them. They're not afraid of failure. A thousand people could witness my son fall on his face without any pants on, and he wouldn't flinch.

It's hard to see this as anything but an advantage. You can't be afraid of looking stupid if you want to be a learning machine. Babies get this. I wish adults could, too.

Morgan Housel is a partner at The Collaborative Fund, behavioral finance expert, and former columnist at The Wall Street Journal and The Motley Fool. He is also also the author of the upcoming book "The Psychology of Money: Timeless Lessons on Wealth, Greed, and Happiness."

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