Everything flows, except piss

The emperor Vespasian knew a thing or two about taxation. The trick was to try and find an activity or goods everybody must have, and then devise a way to make sure people couldn't evade the impost placed upon it. In the emperor's case, he decided that the activity nobody could dispense with was peeing, so he built public toilets, not as a convenience, but as an enforced, and therefore taxed locus for micturition, with heavy penalties for relieving onesself elsewhere. This new tax, a turning on its head of the old vectigal urinae levied on the industrial users of collected urine, probably gave rise to the Latin proverb 'pecunia non olet' (money has no smell). The name of this tax reformer lives on in France in those strange metallic monuments, for men only, the grammatically feminine vespasiennes. Mind you, the average Frenchman of a certain age thinks nothing of urinating anywhere and against anything, particularly churches.

Today, I saw a crowd of anxious ladies in a devastated circle around the entrance to the municipal toilets near the bus station. I went to look, as it is a place where accidents often happen on the slippery tiled steps, and where I had had to help an elderly and very shaken German lady last week. It turned out that the mass protests against Sarkozy's retirement pension reforms included a strike by toilet attendants.

Whether being forced to pee for the good of the imperial treasury, as in the case of Vespasian's unfortunate subjects, or old ladies being denied the opportunity to pee, courtesy of the frequently peeved French public sector, you realise that the effectiveness of decisions relies not so much on absolute coercive power (Britain's grotesquely punitive prison record is an example of how more actually means less) as on the speed with which effects begin to be felt. In the case of toilet denial, the effect is pretty well instantaneous. The ladies got the message...

The saying ascribed to Heraclitus, Πάντα ῥεῖ, [everything flows], was clearly transmitted to posterity incomplete, as there must have been an exception for the contents of the bladder. Πάντα ῥεῖ (oύκ άτερ ούρου). Everything flows (with the exception of piss).