I like to think of myself as a rational human being most of the time, but I have to suppress a shudder if someone opens an umbrella indoors, and I'd probably comment if a black cat crossed my path.
Most people are like this, and most superstitions are harmless. But some bleed into obsession, and I learned of one this week that is so powerful it caused a decrease in Japan's birth rate. It comes around once every 60 years and last happened in 1966; the next time will be 2026. It is the superstition centered around the year of hinoeuma: the fire horse.
Superstition is everywhere. We've seen it recently in soccer players at the Euro 2012 championships in Poland and Ukraine. In some teams it is considered bad luck to shave, and as a result there were some pretty hirsute players running around by the end of the tournament. So I don't want to single Japan out as being especially prone to superstition — but there do seem to be an awful lot of superstitious beliefs in these islands.