Chapter 3 of Turning Signs remarks that humans are capable of a truly sinister dexterity. The joke here is in the etymology of the last two words. Sinister and dexter are the Latin words for left and right respectively. Since the right hand is the more skillful for 90% of humans, dexterity came to mean skill in English. Sinister on the other hand came to mean evil, presumably because we can use good for skillful, as in ‘a good craftsman.’ However the two words lost their symmetry as they diverged in meaning. On the dexter side, we ended up with the paradoxical term ambidextrous, which ‘literally’ means having two right hands – but consider that if someone actually had two hands which were not mirror images of each other, we would surely find it sinister.