Ken Robinson, the one-time professor of education at Oxford University and frequent TED talker, recounts the story of a forum he chaired where one of the participants was the Dalai Lama. He tells of how an audience member asked the Dalai Lama a relatively simple question.

After the question was asked, all eyes turned to His Holiness. After a long pause, the Dalai Lama moved forward in his seat, looked directly at the assembled crowd, took a deep breath and answered: "I don’t know!''

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According to Robinson, this caused silence in the audience and then applause. Robinson himself viewed this as an important moment for himself and the audience - and anyone subsequently listening to a recording of the forum. This was an important moment because the Dalai Lama gave everyone the permission to not know things.

When most of us are asked a question, we feel a reluctance to admit we don't know. We want to know, or perhaps want to be seen to do so. We think that knowing makes us look smart and not knowing makes us look less so. We forget that pretending we know something makes us look downright stupid.

Parents, employers and teachers probably feel this pressure the most. They feel that not knowing damages their credibility as a guru, something they all want to be seen as. We are all like this, to varying degrees.

Knowing is good, but not knowing is also good if it is recognised. No one know everything, and no one likes anyone who thinks they do.  Knowing what you do and don't know is very smart indeed. There is nothing more dangerous than someone who doesn't know what they think they do. Consider US President Donald Trump, the man who appears to know little but claims to know almost everything.

I am a big subscriber to the null hypothesis, a science-related term suggesting that there is simply no evidence available to you that enables you to know.

I cannot believe in God, because there is no evidence of a God. At the same time, I am not a supporter of strident atheists like Sam Harris and Richard Dawkins - since I also see no evidence disproving a God. In the absence of evidence, I simply take the null hypothesis stance.

I am not a believer in astrology, karma, determinism or fate. But again, that is not to say I believe they are all bullshit. I simply have never seen any evidence that any of these notions have any substance in fact or truth.  I have adopted the null hypothesis – a view that there is no evidence to prove or disprove, and as such I have drawn no conclusion at all.

I believe it is folly to pretend we know something when we do not. We cannot know there is a God, because there is no evidence. We cannot know there is no God, because there is no evidence. We cannot know astrology, karma, determinism or fate are real because there is no evidence. Equally, we cannot say they are all bullshit, because there is no evidence of that, either.

In the absence of evidence, it is better to admit to knowing nothing at all.

In this regard, I think of all the fools who "knew" whether Lindy Chamberlain was guilty or not.  None of the people outside the courtrooms had the facts required to know anything – one way or the other.

The null hypothesis is all about accepting the status quo until there is evidence to prove otherwise – while all the time remaining open to that evidence, if and when it comes along. I do not believe in God in the absence of evidence, but I am open to it. I do not believe in astrology, karma, determinism or fate, in the absence of evidence, but i am open to evidence.

Anyone who claims to know any of these things is a fool.

To believe may be okay, but to claim knowledge in the absence of evidence is foolish.