In a few hours, I’m going to be delivering a keynote for about 800 college and university professors. These professors come from a wide variety of disciplines. I arrived at the conference just yesterday, and already I’ve had fascinating conversations about the effect of driverless vehicles on supply chain delivery, big data’s impact on healthcare, and Chinese political history.

As I said, it’s been fascinating.

Now here’s the thing. I’m not an expert on any of these topics. But the people I was talking to are. And, partly because of what I do for a living and partly because I tend to read widely about many topics, I was able to ask questions that were of interest to them.

That’s always been a benchmark for me: to know just enough about virtually any topic that I can ask a question that would interest an expert. Some of my best conversations—and best learning opportunities—have come from this benchmark.

When was the last time you talked to a true expert on a topic outside of your own expertise? If you’re a leader, it shouldn’t be any longer than a week.

This is because a leader should be continually expanding his or her horizons. A leader should be continually learning. A leader should be continually growing.

There are two very good reasons for doing this. (Okay, there are more than two. But I’m only going to talk about two in this article because I’m a bit rushed for time. I’ve got a keynote coming up, you know.)

The first reason that a leader should be expanding his or her horizons is because this is where ideas are born. Ideas are born at the intersection of two or more things (people, experiences, thoughts) that have never been connected before. But if you’ve never come into contact with these people, experiences, or thoughts, you’ll never make that million-dollar connection.

The second reason is because a good leader serves as a role model to his or her team. The best leaders grow other leaders. Whether you’re aware of it or not, your team members are looking to you for cues as to what they should be doing, and how they should be acting. When they see that you are actively engaged in continuous learning, they’ll be inspired to do likewise (the good ones will, that is.)

If you want a simple, step-by-step formula for having a conversation with an expert, here it is:

1. Ask an interesting question.
2. Listen—really listen—to the answer.
3. Ask a follow-up question based on that answer.
4. Repeat

Actually, that’s not a bad formula for any conversation!