The lifespan of humans might be finite, but to Canadian businessman and television personality Kevin O’Leary, work ethic is infinite. On a CNBC “Make It” segment, the enigmatic “Shark Tank” judge pondered his own retirement and came up with a timeframe: never.

“So when am I retiring? Never,” O’Leary said.

O’Leary took apart the concept of FIRE–financial independence, retire early. It’s a common notion circulated among millennials where the sprint to millions or billions of dollars translates to an extended period of doing nothing.

To O’Leary, however, this is a misnomer.

“The idea of financial independence-retire early doesn’t work–let me tell you why,” O’Leary said, hearkening back to his 36-year-old self when he sold his first company and pondered the idea of resting on his laurels, which he eventually followed through on with a three-year hiatus.

“I retired for three years,” O’Leary said. “I was bored out of my mind.”

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The FIRE concept has spawned various strategies promising millennials that workplace doldrums can be temporary. As long as they can endure the short-term pain, they can enjoy the fruits of the long-term gain, but to O’Leary, this is a foreign concept.

Working extends beyond a financial means to an end–it allows an individual to stay sharp mentally. In essence, the grind is not only good for the pocketbook, but for the brain.

“Working is not just about money,” said O’Leary. “People don’t understand this very often until they stop working.”

According to the National Institute on Aging, issues begin to arise as we get into the latter stages of our lives:

  • Increased difficulty finding words and recalling names
  • More problems with multi-tasking
  • Mild decreases in the ability to pay attention

Staying in the workforce or keeping engaged through some form of work can help address these issues. Furthermore, to O’Leary, work defines purpose and establishes the impetus for one’s own existence.

“Work defines who you are,” O’Leary said. “It provides a place where you’re social with people. It gives you interaction with people all day long in an interesting way. It even helps you live longer and is very, very good for brain health.”

“Staying stimulated is how people live into their 90s,” O’Leary added.

So for reasons beyond monetary gain, O’Leary doesn’t foresee himself retiring anytime soon or ever–the big shark tank in the sky included.

“I don’t know where I’m going after I’m dead, but I’ll be working when I get there too,” said O’Leary.

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