Reid Hoffman, the billionaire cofounder of LinkedIn, partner at Greylock, and member of the PayPal Mafia, has emerged as a vocal figure on AI.

Software entrepreneur Reid Hoffman talks about his plan at 12 to change the world, The Start-Up of You, and "the most expensive decision" of his life.

Reid Hoffman is a Silicon Valley power player. He emerged at PayPal, where he was the first full time employee, but is perhaps better known as the co-founder of LinkedIn.