Legendary investor Irving Kahn died on Tuesday. Kahn was a student of Ben Graham and the founder of Kahn Brothers. Kahn even assisted Graham on the classic book, “Security Analysis.” Kahn is one of the original CFAs and he took the exam the first time it was offered in 1963.

“I prefer to be slow and steady,” Kahn said in a 2014 interview with the U.K. Telegraph. “I study companies and think about what they might return over, say, four or five years. If a stock goes down, I have time to weather the storm, maybe buy more at the lower price. If my arguments for the investment haven’t changed, then I should like the stock even more when it goes down.”

“I learned from Ben Graham that one could study financial statements to find stocks that were a ‘dollar selling for 50 cents,’” Kahn told the Telegraph. “He called this the ‘margin of safety’ and it’s still the most important concept related to risk.”

“I would recommend that private investors tune out the prevailing views they hear on the radio, television and the internet. They are not helpful. People say ‘buy low, sell high’, but you cannot do this if you are following the herd.”

“You must have the discipline and temperament to resist your impulses. Human beings have precisely the wrong instincts when it comes to the markets. If you recognise this, you can resist the urge to buy into a rally and sell into a decline. It’s also helpful to remember the power of compounding. You don’t need to stretch for returns to grow your capital over the course of your life.”

Irving Kahn was 109 years old.