The Trees of knowledge/life are located within the human body and are referencing the Central Nervous System. Ancient cultures the world over have symbolically coded this advanced knowledge of the human body and its spiritual mechanisms throughout mythology and scripture, Manly p Hall once wrote. "There are two great systems in the body of man: the tree of life, which is the arterial with its roots in the heart; and, the tree of the knowledge of good and evil, i.e. the nervous system, which has its roots in the brain. These two "trees" are physical manifestations of a complicated network of branching energy currents in the aura or superphysical bodies."