Some of Facebook's early friends now its sharpest critics

NEW YORK (AP) — Some of Facebook's former friends are starting to express some serious doubts about the social network they helped create.

Facebook exploits a "vulnerability in human psychology" to addict its users, Sean Parker, the company's first president, said in a public forum last month. Chamath Palihapitiya, a former Facebook vice president who joined the company in 2007, recently told an audience at Stanford that the company is "ripping apart the social fabric of how society works."

And Roger McNamee, a venture capitalist and early investor in both Facebook and Google, wrote that both companies "threaten public health and democracy" in an August USA Today op-ed .