Bodily Defenses Image Map

Story Time


Walter Cannon (1871-1945)


"Curiosity killed the cat." As a child, Walter had been told that curiosity was a disease and a low vice. He had heard of preachers who said that it was curiosity that created the original sin of Adam and Eve in seeking the forbidden fruit of the Tree of Knowledge. Knowing that could not change Walter from being who he was. He was born curious. Later in his life, Walter came to proclaim that curiosity is a necessity for success in scientific discovery.

Walter was not an egghead. But his father, a manager on the Great Northern Railroad, helped train him to be independent and resourceful in ways that neither of them realized would someday equip Walter to become one of the most famous scientists of all time. As a child, Walter's father refused to buy him toys, even when they had the money to do so. Walter's father was an expert at using tools, and worked with Walter to help him make his own toys. The skill at making toys later translated for Walter into making ingenious devices that were necessary for his experiments on bodily functions. In the picture you see Walter playing with his "big-kid" toys. Maybe you have heard the old saying, "The difference between a man and a boy is the price of his toys!"

None of his ancestors were eggheads either. But his family was restless and even curious. Both on his father's and mother's side, the men and women were always moving into new ventures. Many of his relatives were pioneers on the Canadian and U. S. frontiers. His father, Colbert Cannon, never finished school, because he needed to help support his family during the civil war. After the war, Colbert worked for the Great Northern Railroad and eventually was promoted to the their superintendent of transportation. His hobby was to tinker, always inventing new procedures and devices for the railroad. Unfortunately, his father was prone to bouts of deep depression, which made it difficult for Walter to have a completely happy childhood.

Walter's mother was known for being meticulous - a "neatnik" as we might say today. She also worried a lot and was anxious about little things. Walter did not have many memories of his mother, because when he was only 10, she caught pneumonia and died. One thing Walter never forgot was that on her deathbed she called Walter to her side and said, "Walter, be good to the world."

Few would have guessed that Walter would someday become a famous scientist. When he was 14, Walter was taken out of school by his father, who thought he was doing poorly. Walter worked for his dad's railroad for two years before going back to school and getting serious about learning. Eventually, he became a productive student, but Walter's first love was sports. He especially liked ice skating, hockey, and bobsledding (he grew up in Minnesota and Wisconsin). During warm months, he played football, baseball, and tennis.

His father was concerned about Walter's education. Though uneducated himself, Colbert Cannon knew that education was important and made sure that there was a good supply of books and serious magazines around the house.

Walter was led to science in high school. At that time there was a raging national debate about Charles Darwin's theory of evolution (see other materials in our curriculum). The chief advocate for Darwin was a biologist named Thomas Huxley. Walter became intrigued by these issues and spent many hours reading papers and essays on the topic by Huxley and others. In the process Walter discovered that he understood what he was reading and this motivated him to want to go to college.

One of his teachers, Miss M. J. Newson, an English teacher, took a special interest in Walter and encouraged him. She also helped him get admission and a scholarship to Harvard.

Walter had to work part-time jobs at Harvard. But despite that, he took an over-load of courses, including graduate courses. He graduated in 1896 with high honors. Looking back on his college days, Walter concluded that one of the most important things he learned was how to manage his time. His hectic schedule required him to learn to focus on the task at hand and finish it rapidly and correctly.

Walter was admitted to the Harvard Medical School. Even while going to Medical School, he was hired to teach animal anatomy to non-medical students. Walter finished Medical School in 1900, fulfilling his father's dream that he become a physician. But Walter never became the kind of doctor his father had wanted. In the process of getting a medical education, Walter became more interested in the science of medicine than in the practice of medicine.

In research, Walter had many successes. He discovered much about how digestion occurs and invented the radioactive barium technique for following the movement of food and fluid through the gastro-intestinal tract. He discovered what the adrenal gland does and discovered the adrenalin-like compound that many nerve cells release. He discovered a role for emotions in adrenalin release. He coined the idea of the "fight or flight" control systems of the body. Canon was the first to use the word "stress" in a biological rather than engineering context. He helped explain how the body stays in functional balance through the opposite actions of different parts of the nervous system. This research led him to develop the concept of "homeostasis," which is the idea that normal bodily function requires a steady balance in the function of various organ systems. The lack of such balance, or homeostasis, is disease.

But Walter also had his failures. He spent several years trying to understand the function of the thyroid gland, work that was eventually accomplished by others.

Much of Walter's research was conducted under primitive conditions, even if he was at Harvard. After all, the research was done in the early 1900s when they did not have the "high tech" environments that we have today. He recalls apologizing and complaining to a visitor to Harvard for small, dark, and ill-equipped laboratories, and the visitor replied, "I have never noticed that the nature of the cage determined the singing of the bird."

One thing that Walter did have at Harvard and in the culture of the United States was freedom. In his autobiography, Walter pointed out that other scientists have not fared so well. Galileo, the famous astronomer, was condemned by the Church of his day. Priestly, the discoverer of oxygen, had his home in England ransacked, his material possessions destroyed, and he was forced to flee to the United States. Lavoisier, the famous French chemist, was guillotined by French revolutionaries who had "no need of scholars." Jewish German scientists, including Albert Einstein, were forced to flee Germany prior to World War II.

But science was good to Walter and Walter was good to science. As his dying mother had requested of him, in being good to science, he was good to the world. As the end of his career loomed, Walter took comfort in the words of a poetic colleague, Dr. S. Wier Mitchell:

I know the night is near at hand.

The mists lie low on hill and bay,

The autumn sheaves are dewless, dry;

But I have had the day.




Wolfe, E. L., Barger, A. C., and Benison, S. 2000. Walter B. Cannon: Science and Society. Harvard U. Press, Cambridge.

Cannon, Walter B. 1968. The Way of an Investigator. Hafner, New York.

Cannon, Walter B. 1939. The Wisdom of the Body, 2nd Edition. W. W. Norton. New York.

Introduction | Why It Matters | How We Find Out | What We Know | Story Time
Common Hazards | Activities | Self-Study Game | Teachers Pages | Standards (TEKS)

Peer Curriculum | Organ Systems Home Page | Communication Exercises
Copyright 2001-2003
Web Site Privacy Statement