Embryologist and then Dean of Science, Cy Finnegan, taught a course called Zoology 400, the History and Philosophy of Biology. Themes and concepts from this class, as taught by Cy, and later by Jack, run throughout the book. Mishtu and I joined the "peanut gallery," the group of students and faculty who sat in on Cy's lectures just because they were so interesting. Cy explored ideas ranging from the formal structure of causal explanations to the flash of insight that is part of scientific discovery. Cy and Jack both took a dim view of the suggestion that, because of its complexity, biology should be excused from meeting the same standards of theoretical and empirical rigor as the other natural sciences. They were both skeptical of the neo-Darwinian theory of evolution by natural selection.
The writings of philosopher of science Carl Hempel figured prominently in Cy's lectures, and early on in Zoo 400 he shared a horrific historical tale of hypothesis testing from one of Hempel's books. In the 1840s the physician Ignaz Semmelweis was working in the Vienna General Hospital when he noticed a discrepancy between the First and Second Maternity Divisions. The number of women dying of childbed fever was far greater in the First Division than the Second, and Semmelweis was determined to find out why. He tested a series of hypotheses, either through comparison (even women giving birth in the street had a lower rate of the deadly fever than those in the First Maternity Division) or by experimentation (he had the priest giving last rites change his route in case his presence was depressing some of the women and making them susceptible to disease). Semmelweis spent three years testing every possibility he could think of, but to no avail. New physicians were trained at the hospital and one day during an autopsy a medical student slipped, accidentally stabbing one of Semmelweis's colleagues in the hand with a scalpel. After showing all the symptoms of childbed fever, the instructing physician died. In those days, an understanding of disease causing bacteria was a thing of the future and physicians hardly bothered to wash their hands after leaving the morgue. In the Second Maternity Division, midwives delivered the babies, but in the First Division, teaching staff and students assisted. Semmelweis conducted a final experiment where he had everyone engage in serious hand washing before touching women in labor. The childbed fever rate in the First Maternity Division quickly dropped.