Mark Divine opened SEAL Fit, a Navy SEAL preparation center in California, in response to the stark proposition candidates faced: 90 percent will fail if left to their own devices. Fortunately, Divine has the key for bolstering their mental toughness and dramatically increasing their odds for success. He took the same journey himself after leaving a stable but miserable career as a certified public accountant.

In this video, Divine talks to Joe De Sena of the Spartan UP! podcast series about what he found along the way and challenges the host to a brutal workout. According to Divine, philosophies similar to those of gentle spirits such as the Dalai Lama and Eckhart Tolle are a more effective way to grit than those of the average drill sergeant.

Lessons learned include:
1. The human spirit soars when it's challenged.
2. Life is made up of the small choices you make from moment to moment, rarely the big ones.
3. The essence of mental toughness is to notice when you unconsciously make the wrong choices.
4. The most important lesson for mental toughness is to know your "why."

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