We all know a know-all – someone who believes that they possess a superior intellect and wealth of knowledge, and who shows a determination to demonstrate that superiority at every opportunity. In a world where knowledge is power, the know-alls should be ruling the planet.

Yet it seems to be one of those truisms, that the more know-all someone is, the further they are from actually running things. After all, if they knew it all, they would know that it’s the worst sort of rudeness to let everyone else hear about it. On the contrary, the get-aheads often seem unencumbered by sacks of facts. While the know-alls are relentlessly exhibiting the sum of their knowledge, the get-aheads are far too busy getting on with the job in hand to waste time pointlessly showing off.

Sometimes a know-all will stray, unknowingly, into your own area of expertise or experience, facing you with a dilemma. You can either sit back with a superior smile on your face, wait for them to get tangled in some half-understood detail, and then trip them up with a devastating display of knowledge. But that kind of social humiliation is cruel and does not reflect well on you. At the other end of spectrum, you can sit meekly, nodding assent as they mutilate your specialist subject with untruths and unsupported assertions.

It is better, inevitably, to take the middle way; as soon as you see the know-all blundering into your knowledge zone, just give them a little hint that they’re in dangerous territory, for example politely mentioning that the subject in hand is a particular passion, or something you have studied in detail, or something that you have experienced yourself. It is important that you clarify your superior knowledge and give them an escape option before they dig their own grave. If they plough on regardless, then they do so at their own peril – they have been warned.

We all love trivia, useless knowledge and the occasional weird feats of memory, but most of us have the sense to realise that it is not clever to trumpet such empty expertise. It’s fine to dredge up arcane knowledge at a dinner party if people find it intriguing or amusing, but beware – entertaining your friends with amusing trivia can all too often mutate into boring your friends with tedious irrelevancies, so watch out for the glazed eyes and stifled yawns.

If you are faced with a know-all, pity them for their lack of self-awareness, and listen intently to their verbal bludgeoning for the odd interesting fact. When you feel you’ve travelled as far as you reasonably can into the dull vistas of the know-all’s inner world, move on politely, leaving them, and their empty knowledge, behind you as you get on with real life.

TOP TIPS

• Remember that the more know-all someone is, the further they are from actually running things.

• Endless displays of empty expertise are likely to bore an audience to death, revealing only the know-all’s own feelings of self-importance.

• If you are faced with a know-all, pity their lack of self-awareness.

• If a know-all strays into your own area of expertise, subtly give them fair warning – failing to extricate themselves may have humiliating consequences.