An essential nutrient is a nutrient required for normal body functioning that can not be synthesized by the body. Categories of essential nutrient include vitamins, dietary minerals, essential fatty acids and essential amino acids.
The Neolithic men (and women) had huge nasal cavities so they had a superior sense of smell; they adapted to use their teeth as weapons, like for tearing flesh or sharpening wood; and they all adapted to making weapons and tools out of wood and stone, some better and sharper than the ones we have today.
In this case, dr. Xavier is using: free association to treat his client
In a free association method, a psychologist will try to find the underlying cause of the problem by letting the patient share his/her thought.
From the patient's story, Dr. Xavier could determine the way patient thinks and determine which way of thinking cause the patient's disorder