Searching for the Source of the Soul 1907 – Body, Soul and 21 Grams

Looking to the future, believing that a mind could be simulated or uploaded to a computer as we learn more about brain structure is a materialist view that assumes mental activity originates in the brain. 

By contrast, in the mid-1600s, the French philosopher René Descartes proposed that the “mind” or “soul” existed separately from the brain but was connected to it through an organ. This organ acted as a portal between brain and mind. The ancient Greek physician Herophilus, who believed that the soul occupied a fluid-filled space in the brain, said it was located specifically in the calamus scriptorius, a region at the floor of the fourth cerebral ventricle.

In 1907, the American physician Duncan MacDougall placed dying tuberculosis patients on a scale. He believed that, at death, the scale should show a drop in weight as the soul left the body. From his experiments, MacDougall measured the soul at 21 grams (0.7 ounces). Unfortunately, neither MacDougall nor other researchers could reproduce this finding.

These different views about the distinction between soul and matter have given rise, in the philosophy of mind, to the idea that mental functions are not physical or that mind and body can be separated (Mind–Body Dualism).

A materialist view holds that the mind and body are interconnected and that changes in the brain can affect thought, memory and personality. Brain imaging studies show how particular thoughts and emotions are represented in the brain.

Gourmand syndrome is an example that supports this view. Damage to the right frontal lobe of the brain can cause dramatic changes in a person's eating habits and preferences. This syndrome develops as a result of brain damage and may lead a person to develop an excessive interest in luxury and gourmet foods.

This information can help us understand the complex relationship between brain and mind and offers an important example of how behavioral changes can emerge after brain injury. It is valuable information for professionals working in neurology, psychology and medicine.

Historical Figures Mentioned in the Article: Herophilus of Chalcedon (335 B.C.–280 B.C.), René Descartes (1596–1650), Duncan MacDougall (1866–1920)

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