Melvin H Green, University of California, San Diego My mother cried when I told her I was changing my major from engineering to chemistry. Her fear was that I would never earn a living as a chemist. When she heard a few years later that I planned to go for a PhD in chemistry, her only comment was, So why don’t you at least become a real doctor? Doctor, lawyer, engineer – these were careers that Eastern European immigrants such as my mother and father knew had definite earning power. Having survived the Great Depression, they believed earning a living …