From Sam Warburton
Your articles on nudge, the art of subtle persuasion, used the example of the aim-inducing fly etched in urinals to ensure cleaner bathrooms (22 June, p 32). There is an earlier version: in the 19th century the picture was a bee. This combined practicality with a mild joke. The Latin for “bee” is Apis.
Penarth, South Glamorgan, UK
