When “Tools of Titans” author and podcaster Tim Ferriss was asked on a book tour pit stop what he would print on a billboard if given the chance, the self-help guru did not hesitate.

“You are the average of the five people you most associate with,” Ferriss answered.

During a talk at the San Francisco headquarters of e-book and audiobook subscription service, Scribd, Ferriss shared a piece of advice that was given to him as a teenager. It riffs on a now famous tip from motivational speaker — and early Tony Robbins mentor — Jim Rohn.

The rule suggests that the five people you spend the most time with shape who you are. It borrows from the law of averages, which is the theory that “the result of any given situation will be the average of all outcomes.” We might interact with many people, but the few who are closest to us have the greatest impact on our way of thinking and our decisions.

“I was given that advice probably when I was 15 or 16, which has impacted a lot of my decisions since,” Ferriss said. “And each year, I think it is more and more important.”

In an interview with Business Insider last fall, Ferriss rattled off the names of a few people he cycles into his inner circle. Matt Wullenweg, a lead developer of WordPress, and serial entrepreneur Kevin Rose made the short list. As did Kevin Kelly, the founding executive editor of “Wired” magazine, who Ferriss also called the “true world’s most interesting man.”

“Then there are people like Maria Popova, who I’ve gotten to know,” Ferris told Business Insider. “Her ability to consume high quality information and distill it, and then put out beautiful prose gives me something to aspire to.”

He topped off his current five with the godfather of self-help and author of “Unlimited Power,” Tony Robbins. “The more I get to know him, the more impressed I am,” Ferriss said.

On stage at the Scribd office, Ferriss explained that the list is ever-changing, depending on what areas in his life he wants to work on: physical, emotional, psychological, or financial.

“If I feel like I need more work in the physical realm, then I’ll modify the group to reflect that,” Ferris said. “It’s not always the same five.”

You can learn more of Ferriss’ life hacks in his new book, “Tools of Titans.”

Originally published at www.businessinsider.com

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