Dave Snowden, 'knowledge management' whizz and a lot more besides, runs an interesting blog called Cognitive Edge. One of his recent posts mentioned Bertrand Russell's observation:

"If a man is offered a fact which goes against his instincts, he will scrutinize it closely, and unless the evidence is overwhelming, he will refuse to believe it. If, on the other hand, he is offered something which affords a reason for acting in accordance to his instincts, he will accept it even on the slightest evidence."

This is exactly what happened with the Quechup social networking invite which I mentioned last week. People were getting invites from their friends, or so they thought, and they signed up without a moment's hesitation. The evidence, in this case, was the fact the mail appeared to come from a friend, when it didn't.

Here's a more recent example. A story from Peninsular Business Services, which was swallowed whole by the BBC on Tuesday:

"233m hours are lost a month due to workers wasting employers’ time on social networking sites such as Facebook. The problem will cost employers £30.8bn per year and is to escalate."

From a sample probe of one, I learnt that people in the BBC are 'addicted' to Facebook. But whether the time spent on it is 'wasted' or actually time-saving, I have no idea. And I don't suppose Peninsular knows either. But it certainly knows how to produce a scary headline and frighten businesses into shunning social networking.

I tried to do the maths: if 47 percent (Sigurd Rinde came up with that one) of the 60-odd million people in the UK work, if they all used social software and if Peninsular's figures were true, they'd 'waste' just over eight hours a month each. Say two hours per week. Assuming a 36-hour week, anything below a 5.5% penetration would mean that users of social software do nothing else while at work.

Dennis Howlett, who waxed lyrical on this subject, reckons that fewer than one percent of employees use social networking sites at work. This would suggest that Peninsular's figures are very very wrong. It would mean those that had access would be spending over forty hours per day being social online.

Yet, returning to Bertrand Russell, I bet people believed them and their implications because it fitted their instincts.