What Keynes wrote in 1936 about economics is just as true of advertising: "So-called practical men, who have never knowingly been exposed to an intellectual influence in their lives, are invariably the slaves of some defunct economist"... It's only by understanding the historical roots of the assumptions we make about advertising that we can begin to free ourselves from being Keynesian 'slaves' to those assumptions. It's only when we realise that none of these theories, models or metaphors represents absolute truth, but is one of many 'ways of seeing'... that we can make use of any of them as a source of inspiration rather than be confined by it.

Paul Feldwick, The Anatomy of Humbug: How To Think Differently About Advertising