In an interview with author and entrepreneur Tim Ferriss, professional poker player Annie Duke says that when you’re trying to find out what’s true about some issue, it helps to seek out dissenting ideas and opinions.

For Duke, this is especially true with strongly held views: “The fact is that when two extreme opinions meet, the truth lies generally somewhere in the middle.” 

Without exposure to the other side, you will naturally drift toward one extreme and away from the truth. 

What holds many people back from this approach is the fear of being wrong. But as Duke puts it, instead of being fearful, you should feel good about truly hearing those who disagree with you. 

After all, “being wrong is just an opportunity to find more of the truth.”

Retired US Army four-star general Stanley McChrystal says in an interview that one problem with creating a plan to solve some problem you’re facing is that you’ll start to fall in love with it.

You begin to dismiss the plan’s shortcomings. And sometimes you’ll find yourself “skipping over real challenges to it, or vulnerabilities in it, because you just want it to work.”

To keep yourself honest, and to more accurately test your plan’s validity, McChrystal recommends creating a “red team.” 

The more thoughtful your red team is, the better the results will be.

Marketing guru Seth Godin writes on his blog that competition can be a useful signal: “It means you’re offering something that’s not crazy.”

For example, the busiest Indian food restaurants in New York City are all within a block or two of each other. 

And books sell best in bookstores, “surrounded by other books, their ostensible competition.”

If you have no competition, Godin’s recommendation is to go find some.

“The only true voyage of discovery, the only fountain of Eternal Youth, would be not to visit strange lands but to possess other eyes …“

- Writer Marcel Proust in his book Remembrance of Things Past