Some of the people who made Facebook what it is today have become the loudest voices speaking out against social media. Chamath Palihapitiya, former vice-president of user growth, said the tools he has built are " ripping apart the social fabric of how society works." He added that he feels "tremendous guilt" for his role in Facebook's rise, saying: "The short-term, dopamine-driven feedback loops that we have created are destroying how society works. No civil discourse, no cooperation, misinformation, mistruth." Sean Parker, Facebook's founding president, admitted that his work exploits "a vulnerability in human psychology." He added: "It literally changes your relationship with society, with each other. It probably interferes with productivity in weird ways. God only knows what it's doing to our children's brains." And Antonio García Martínez, a former product manager, has claimed that Facebook has gained immense power through its targeted ads.