Half-Witted or Heroic? Man Fights Off Shark, Sutures His Own Wounds, Then Throws Back a Beer If you thought building a business required resilience, consider the tale of a 24-year-old New Zealand doctor who fought off a shark attack, sutured his own wounds and then threw back a beer.

BIZ Experiencess are resilient creatures by nature, but even the toughest of them can sometimes feel lost at sea. After all, building a business -- one that ostensibly could change the world -- is a process full of emotional highs and lows. One second you're the smartest person in the room; the next, you're questioning whether you know anything at all.

Which is why it's important to remember that BIZ Experiencesship, at its very core, is about determination. Determination in the face of challenges of all kinds. Determination that might seem, well, kind of bonkers.

A striking reminder of that kind of determination is in the tale of James Grant. After a shark latched onto the 24-year-old's leg during a spearfishing expedition last Saturday, he reacted with either exultant courage or brazen disregard -- or a little bit of both. The New Zealand doctor jabbed the shark with his fishing dagger, stitched up the lacerations with his own first aid kit and then walked to a nearby bar to soak up his dripping wound with a bandage. To dull the pain, he was kindly offered a beer.

Related: Afraid of Sharks? No Problem. Just Check Twitter.

Talk about taking things in stride.

Even Grant himself seemed startled by the audacity of his composure. "To be honest it was a bit of an odd reaction," he told Radio New Zealand. "It wasn't really fear or anything, it was just like: 'Fuck it, I've got to try and get this thing off my leg.'"

And Grant's friends were equally nonplussed, as he tells it -- they simply continued fishing despite his calls for help ashore. Thankfully, he was wearing a neoprene wetsuit that was 7 millimeters thick and just happened to have a first aid kit in his car for use during pig hunting expeditions, which allowed him to temporarily suture the 5 cm gashes on the back of his leg himself.

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(Unfortunately for him, the sevengill shark whom Grant suspects attacked him had not been outfitted with a Twitter chip.)

"I sort of tacked it together with a couple of stitches," Grant said. "I think I must have been adrenalized at the time, because I wasn't too bad putting them in -- but I wouldn't usually do that."

When faced with seemingly insurmountable challenges, in other words, the truly triumphant tap into a sense of transcendent strength they didn't even know they had.

And the next time you're thinking about taking a day off, consider this: After being sent off to the hospital to finish of his stitches, Grant was back at work the following Monday.

Related: Steve Jobs: Victim of His Own Dogged Determination?