We need a way to distinguish real science from rumour on the web, sais Tim Berners-Lee, the creator of the web. "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." True. It is a problem. But it is not a problem limited to the web, as the spread of tabloid journalism and politicized news channels demonstrates. As Al Gore says, society is facing a problem of how to distinguish the real from the fake generally.