"It is the mark of an educated mind to be able to entertain a thought without accepting it."

This is how I exercise that skill. I listen to science, sociology, religion, conspiracy theories, relationship dynamics, etc.

Sometimes, I pick up something. Most of the time I'm allowing the ideas to float around in my head.

It helps a lot to practice this skill, because I trade for a living and I need to be able to convince myself that I am wrong about something all the time.