"On the web the thinking of cults can spread very rapidly and suddenly a cult which was 12 people who had some deep personal issues suddenly find a formula which is very believable," he said. "A sort of conspiracy theory of sorts and which you can imagine spreading to thousands of people and being deeply damaging."
Sir Tim spoke to the BBC last week, to publicise the launch of his World Wide Web Foundation which aims to improve the web's accessibility.
Alongside this role it will aim to make it easier for people to get online. Currently only 20% of the world's population have access to the web. "Has it been designed by the West for the West?" asked Sir Tim.
"Has it been designed for the executive and the teenager in the modern city with a smart phone in their pocket? If you are in a rural community do you need a different kind of web with different kinds of facilities?"
(Read the whole story on the BBC website.)
The world isn't going to end for a couple of months though (as far as I know) because the Large Hadron Collider has been switched off - some kind of magnet problem apparently - so we can all breathe a big sigh of relief.