These Founders (Really) Fight

Alex Tehrani
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"It's Just Primal"

"I had done some marshal arts as a kid, but I felt this kind of urge to experience actually being in a fight. I want to experience all the things it means to be human. It's just primal," says Lukas Biewald (facing the camera here), the founder of San Francisco crowdsourcing start-up Crowdflower. "I think founders of companies in general really value new experiences, and really thrive in competition."