Basically the Nobel laureate,–who despite giving interviews to blogs and having his writing published on sites like Sahara Reporters (which wouldn’t have existed, but for the internet)–hates all social media:

“… Let me take this opportunity to announce yet again that I do not tweet, blog or whatever goes on in this increasingly promiscuous medium. I do not run a Facebook, even though I am aware that one or two serious-minded individuals/groups have instituted some such forum on their own, for the purpose of disseminating factual information on my activities. I neither contribute to, nor comment on the contents of their calendar … To speak generally, Internet abuse is getting to be a universal plague, one that goes beyond personal embarrassment and umbrage. I strongly recommend collective, professional action to protect the integrity of the medium, and save it from becoming a mere vomitorium for unprincipled scallywags with, or even with no particular axe to grind.”

Source.