Jorge Vieyra from Mexico is following a PhD in applied physics. Hardly have we explained the idea underlying the ‘I wonder…’ feature in Cursor, when he shows great enthusiasm. “I know something, I have something! Why is there often a fly printed in the urinoirs in men’s toilets in cafés or other public facilities?”

Sphinx Sanitary Ware together with Schiphol in 1992 designed the urinal with the built-in fly, as a solution to the often very filthy men’s urinals. That fly has been printed for men to take aim better. Men tend to pee in a slightly neater way if they have a target: aim at the fly as best they can.

This explanation does not satisfy Vieyra: “I understand that the fly is there to aim at, but why a fly? Why not something else?” The most plausible reason that we have been able to come up with for the choice of a fly is that men want to try and make this fly take off, which explains why they aim so accurately. This probably works only once, for when you have found out that the fly is a fake, the fun is gone. Then there are also people who wonder whether the fly does not bring about the opposite effect in animal lovers, because they try to avoid the fly at all costs.

Meanwhile individual peeing stickers of various kinds can be ordered, such as politicians’ faces or popular comic characters. (HB)