In this segment of the Rule Breaker Investing podcast, David Gardner unearths a bit of wisdom from William Temple, who was, during World War II, the Archbishop of Canterbury. Temple's quote speaks to the value of intellectual curiosity, as well as humility -- two things that are vital for anyone looking to succeed in investing -- or almost anything else, for that matter.

A full transcript follows the video.

This video was recorded on Aug. 16, 2017.

David Gardner: All right, and quote No. 5. Quote No. 5 comes from Archbishop William Temple. Now, I don't know a lot about Archbishop William Temple. I did do a little cursory research, so I was ready for this podcast. I can tell you that he was born in 1881. He died in 1944. He was, at one point, the Archbishop of Canterbury, a very august position in Great Britain.

He had some great lines. Most people who have a great line probably, like roaches, there are other ones out there, too. Benjamin Franklin has a great line. It turns out he had hundreds of them, especially if you start reading Poor Richard's Almanac. So, these kinds of people are often "machines." In fact, here's one that I see referenced on the internet.

I can't verify it, but it says that William Temple said this. This is not my quote. I'll be sharing my favorite quote in a sec, but here's one. "The only way for a rich man to be healthy is by exercise and abstinence. To live as if he were poor." Food for thought. I like it, William Temple.

And I should mention briefly that this comes from a religious figure. Religion is not something that is often discussed, either in polite circles these days or in general ways. In some ways, religion has been pushed off onto the sides, and only the fringe feels like it can talk about it. I'll just mention very briefly that I try to go to church each week. I highly recommend the practice, regardless of what faith you have.

Sometimes we're described as a faithless world or a post-religious world. I don't think that's what we are. I don't think the numbers actually suggest that, but I certainly know that in lot of areas of the world, going to church sounds like something dowdy or old-school. But I do appreciate what I think about and the opportunity for reflection that I have each week in church, and so people like William Temple I'm going to be somewhat positively oriented toward, especially when they develop five-star quotations like the one I'm about to share with you.

But before I share that, and I don't mean to keep dragging this out like a Motley Fool marketing video, but I'm -- but I should mention one other great quote. This also comes from a church figure. William Ellery Channing was the foremost Unitarian preacher in the U.S. back in the early 19th century. It's about loneliness. I thought this was great.

He said, "People are lonely because they build walls instead of bridges." Love it. As you can see, I think I've done this in past "Great Quotes, Volume X" series. Sometimes you get a few more quotes than just the five that I'm sharing.

Anyway, now back to the Archbishop William Temple quote, and here it is: "The greater the island of knowledge, the longer the coastline of mystery." The greater the island of knowledge, the longer the coastline of mystery.

Why do I love that quote? Why do you maybe love that quote? I think it's because it reminds us how big the world is and how valuable intellectual curiosity really is. There are so many things to learn in this world. I've been trying to read The Economist once a week. I can't get through more than about one-half to one-third of it in a given week before the next one comes out, and I'm trying to read other things, too. There are so many things that we can try to learn.

I think I mentioned earlier this summer that I've turned off regular news feeds in my life, so I no longer check the Google news page X times a day. Or as I drive into work, if I'm not listening to a Motley Fool podcast, I'm no longer listening to the local news spinning back every half hour. These kinds of things. I've just kind of said, "No, I don't want to be too distracted by that." But even then I can't get through all the things that I want to learn. Maybe you feel like you can't, either.

After all, one of the themes of this week's podcast is we do have a lot of choices, don't we? But given that, how rich it is for you and me to have intellectual curiosity. To have that burning bright -- that flame burning bright. Always fascinated. And then to think that "the greater the island of knowledge, the longer the coastline of mystery."

And beyond just the poetry and the imagery of that lovely phrase, Archbishop William Temple, I think is the humility that is implicit within it. Because most people, I think, expect that as they gain knowledge they become more authoritative. Some people might start calling them experts. Nobody really ever calls me an expert. That's one of the reasons I love calling myself a fool -- maybe you do, too -- because I don't want people to overrate my knowledge or my authority.

So in a world where often you'd assume that people who have built up a huge island of knowledge would be a little too proud, in some cases, beyond just being an authority, we're reminded that "the longer the coastline of mystery," the more you know, I guess we could paraphrase, the more you know you don't know. And the humility, as I say, that's implicit in that concept is very true -- it's very true -- is important for all of us.

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