Prague is a city of unwritten rules. Thou shalt not stand on the left side of the escalator, although this is nowhere to be found on a sign in the metro stations. It’s just how it is done. Thou shalt have exact or close to exact change when paying for anything, unless you want to subject yourself to the fearsome glare of the waiter who must now go off to find change. While on a train last weekend, I watched the conductor ask the other passengers in the train car if anyone had change for a 200 crown note. Fully half the passengers patiently hauled out their wallets and searched for change. It is simply well-known that no one selling anything carries a great deal of change, as this is the responsibility of the buyer. If you are buying produce at the grocery store, it is important to weigh your fruits and veggies and get the printed price tags from the electronic scale, or you will find yourself holding up a line at the checkout while you race back to the produce section. Also, parks here do not close at dusk to reduce to possibility of a visitor falling in the dark and suing the state. This general situation is covered under the unwritten eleventh commandment, thou shalt not be stupid. This commandment is hauled out at various times, to deal with everything from jaywalking to racing down escalators. One Sunday morning, I watched a local resident berate a pair of tourists for failing to yield the open center space of the metro train to a couple with a stroller (this is standard procedure in metro trains, as this open space is generally the only space wide enough for strollers).The tourists, unfazed by this diatribe delivered in Czech, shrugged in confusion and resumed eating their slices of pizza. The local resident then switched to English to deliver his verdict of ‘tourists’. In addition, thou shalt remember that Thursday is called ‘little Friday’ for a good reason, and not expect any emails written after lunch on Thursday to be returned until Monday. This rule also holds true when a national holiday falls on a Thursday, in which case the Wednesday before then becomes a partial holiday. If you have any official business to get done that week, it’s best to start early. Tipping is not a set ten or fifteen percent, but often a rounding up to the nearest hundred crowns. If your waiter was terrible, it is acceptable to leave a one crown tip. But never shalt thou bow to the demands of your waiter for a set fifteen or twenty percent tip. At this point it is best to flee, and find another restaurant to frequent. Finally, thou must remember that Czech bureaucracy is unfathomable at best. If you ever find yourself filing forms in quadruplicate, it is best not to inquire exactly why. I’d continue, but my cat is glaring at me. Apparently it is tradition that I give out kitty treats within ten minutes of coming home. Another unwritten rule I must learn.