The quickest way to ruin a meeting, it's been said, is to ask everyone around the table how they think advertising works.
Because no two individuals would agree.
And frankly, this is an embarrassment.
Can you imagine plumbers sitting around, arguing about 'how plumbing works'? Lawyers may disagree on the facts of a case, but they all have a very clear understanding of what the law is. Knife-makers agree how knives work. And bakers all know how bread is made.
Almost unbelievably, some of our theories directly contradict each other. For example, some argue it is essential that advertising has impact - if you don't 'cut through the clutter', your message won't be heard. But others argue that the brain works mostly by Low Involvement Processing - we process marketing messages at least as much when we are paying little attention to them as we do when we consciously take them on board, so cut-through is irrelevant.
I was intrigued, therefore, as to whether 'the answer' would appear in the book that uber-strategist Paul Feldwick has just published called 'The Anatomy of Humbug'.
It's billed as "a book that isn't about how advertising works, but about how people think advertising works."
My copy hasn't arrived yet, but I have to say that the interviews Mr Feldwick has done to promote the book - while fascinating - have left me seriously depressed.
I suppose I've long cleaved to the hope that although we may disagree right now about how advertising works, there will be an answer 'one day'.
Mr Feldwick seems to imply not.
While according to one reviewer "he sidles very close to answering the fundamental question" he eventually concludes "there isn't an answer" and admits that "the book supports multiple points of view."
Most worryingly of all, he talks about the need to 'respect other people's beliefs'.
And that, my friends, is not the language of science, or of art... but of religion.