"His ability to boil things down, to just work on the things that really count, to think through the basics... It's a special form of genius."

-- Bill Gates on what he's learned from mentor Warren Buffett, as told to Fortune in this week's Best Advice issue. Of all the great advice the Microsoft (MSFT) founder has gotten from Buffett -- his greatest mentor besides his dad -- "one of the most interesting is how he keeps things simple," he says. "You look at his calendar, it's pretty simple."

The same philosophy guides the Berkshire Hathaway (BRKB) chief's business moves. Gates explains, "You talk to him about a case where he thinks a business is attractive, and he knows a few basic numbers and facts about it. He picks the things that he's got a model of, a model that really is predictive and that's going to continue to work over a long-term period."

Simplicity never goes out of style -- but we do need to be reminded to get back to basics. Time Inc. built a successful magazine on this theme: Real Simple. The concept of "keeping it simple" is also universal. It's the message Pattie often turns to when advising me on my writing for Postcards. And as you'll read in the issue, this is also the best advice that the world's No. 1 golfer got from his dad. --Jessica Shambora