I was reading about Fritz Haber yesterday. He was the German Jewish chemist who invented a way of creating ammonia. The book says that the fact so many of us are alive today is largely down to this process, because the limiting factor in agriculture previous to the 20th century was the limit in soil nitrates. Without nitrate fertilisers derived from ammonia, the planet would only support 3.5 billion of us. Fritz Haber was awarded a Nobel prize in 1920. However, Fritz Haber, being a very patriotic German, took it upon himself to synthesize poison gases for weapons during World War 1. It was him who found a way of synthesizing chlorine gas that Wilfred Owen complained about. His wife shot herself in the head with his service revolver when he refused to stop making them. He died in the 1930s as the Nazis were taking over Germany. I do not know whether Fritz Haber was a very reflective man, but he must have had a lot to ponder on in his last years.