It's important to have friends who you know are smarter than you.

They help you intuit your own intelligence's limits, and how to strive to achieve more within them.

Because they are your friends (as opposed to, say, your boss) it inspires you without intimidating you.

If you are smarter than all of your friends, you might fail to realize where your limits are, and you might become closed to disconfirming evidence.

If you're powerful, sometimes your friends are smarter than you… but still defer to you even when they're right.

People are spiky; no one is the most intelligent in every dimension.

Surround yourself with people who collectively outclass you in as many dimensions as you can.