David Hubel | Nov 14, 1993 | 6 min read
When I was a medical student in the late 1940s, we did weekly laboratory exercises in physiology and pharmacology. Each group of four students would anesthetize a cat or dog and do an experiment, investigating blood pressure or respiration or recording electrical activity from the brain. That was where we learned how complicated a live animal is, where we learned to cut and sew up skin, where we learned to control the loss of blood, and where we got over some of our squeamishness at the sight o