Lecture VI
Let us now go on to consider the second man. We shall best understand the second man if we pursue the following train of thought. The essential organ of the head is, as you will easily see, the brain. Now man has something else in his form that is similar to the brain. It differs from the brain of the head in what is apparently a detail, but really a point of great significance. Man has actually something like a second brain; it is the brain of the spinal cord, which is enclosed in the spinal column.
Read this passage in another edition
DEoriginalENEnglish