The omnipotent buying public carries in its mind only a dim conception of the part played in its daily life by this enormous new pseudoscience, advertising. How did that tube of Pepsodent toothpaste, for instance, reach your bathroom shelf?…It got there, obviously, because somehow Lord & Thomas had at least made you suspect that of all toothpastes Pepsodent is the one most imperative to your health and happiness. You may not remember but somewhere you read that you had a film on your teeth and that gritty Pepsodent was the thing which would polish that film away.

Tim Wu, The Attention Merchants, loc. 194