My wife calls me a baby orangutan, maybe you can see why? 😄 My last hair cut was February 13th: 142 days ago, or approximately 20 weeks. Today I’m going to get it cut. I normally get it cut every 5 weeks. After the last cut I was certain I would get it cut again within 5 weeks. It didn’t happen. Hardly a disaster of course but it got me thinking about certainty, and the uncertainty I feel about getting it cut today. In science certainty and uncertainty are probabilistic, sta