370. It should be noted that the forms themselves of a person's members, organs and viscera are, as to their essential structure, the product of fibers arising from their first elements in the brain, but that they are given fixity by such substances and materials as exist in the earth and from the earth in the air and ether, which is effectuated by means of the blood. Consequently, for all the constituents of the body to remain in their formation and so continue in their functions, a person must be sustained with material food and be continually renewed.