I learned a lot in my four years at university, but I can’t explain why some of what I learned has long receded from my memory and some remains crystal-clear. I could tell you all about Haussman’s Paris, and quite a lot about Georges Seurat, and a fair amount about new towns. But I spent as long learning about German Expressionism as I did any of those other things, and of that once-treasured knowledge I have retained exactly nothing.

The most useful thing I learned at university, though, didn’t have anything to do with my degree course, and I am delighted to be able to pass it on to you now, having been reminded of it this morning by a job advertisement that was looking for “committed and capable” candidates. With lifelong gratitude to Professor Peter Vergo, who taught it to me, I present you with The Reverse Bullshit Principle.

The reverse bullshit principle (you need only cap it up the first time) holds that if, when the sentiments contained in a given statement are reversed, the statement becomes ridiculous, then it wasn’t worth making to begin with.

For example, this sentence, taken from a different job advert:

In addition, the applicant must want to be a contributor on a team that strives for excellence and continuous improvement on a daily basis.

Could, when subjected to the reverse bullshit principle, be rewritten thus:

In addition, the applicant must want to be a contributor on a team that strives for mediocrity and sporadic improvement on an infrequent basis.

As the example illustrates, if the opposite of what you’re saying is clearly ridiculous, then what you’re saying should – well, it should go without saying.

The use of the reverse bullshit principle makes it easier to work out when someone is spouting nonsense for the sake of making a noise, rather than because they have anything worth saying. It is useful in all walks of life, but writers in particular should take careful note of it. When I worked in a bookshop we used to sell a remarkably high number of copies of a book called The Career Guide for Creative And Unconventional People (I am linking to it so you can see the font they used for the front cover, which should have provided a clue if nothing else did that this was not a volume worth reading). I longed for the day when someone would come in and say “Ah, but I’m unimaginative and ordinary, so that’s not the book for me!”.

Tomorrow, when I am at home and have the relevant volume with me (I need to quote from Vasari), I will tell you about the second most interesting thing I learned at university.