There is little sense in testing advertising efforts without having a theory about what advertising is supposed to do. It is equally without much sense to pre-test advertisements (or elements that would go into advertisements like themes, artwork, slogans etc.) without assumptions about what post-testing of the same advertisements is supposed to show. And finally: theories that cannot be tested for proof or disproof are not very useful. It should also be realised that in most fields of scientific endeavour the theories have followed rather than preceded every day life and observations of what went on in actual practice.