The Energies of Life

     The human body and all its faculties, organs and systems function on energy, which is distilled, generated and supplied by the organism itself.  Without energy to animate it, there is no life.
     There are two basic types of energy in the human organism: kinetic and thermal.  Kinetic energy is responsible for all function and movement, whereas thermal energy is responsible for all digestion, metabolism and transformation.    Life requires both kinetic and thermal energy.
     Greek Medicine calls kinetic energy Pneuma, or the Breath of Life.  Pneuma is similar to what Chinese Medicine calls Qi and yoga and Ayurveda call Prana.
     Greek Medicine calls thermal energy Ignis, which is Latin for Fire.  Ignis is similar to what Chinese Medicine calls Yang or Huo and to what yoga and Ayurveda call Agni. 
     As they are generated, and subsequently flow and are distributed throughout the various faculties and systems of the organism, both Pneuma and Ignis assume various forms.  The essence of these vital energies remains the same, but the functions they are adapted to perform change.
     All the major bodily functions have both a kinetic and a thermal aspect.  Take digestion, for example:  Its kinetic aspect is the churning and peristalsis of the stomach and intestines, whereas its thermal aspect is the distillation, generation and metabolism of the humors.


The Three Forms of Pneuma

     Pneuma, or the Breath of Life, is initially extracted from the air we breathe by the lungs, which then send this raw pneuma to the heart.  There, it is combusted and infused into the blood, assuming a very potent and concentrated form.  This is the Pneuma zoticon, or Vital Force, which is the basic, primal form of pneuma in the organism.  This Vital force is the pneuma of the Vital Faculty, where its main functions are to power the circulation of blood and cellular metabolism.  This Pneuma zoticon is then changed into other forms of pneuma by the principal organs of the other faculties.
     In the liver, the Vital Force is changed into Pneuma physicon, or the Natural Force, which is the basic form of pneuma for the Natural Faculty.  When the liver infuses this Natural Force into the Four Humors upon their generation, this Natural Force is then differentiated into four different subforms, called the Four Administering Virtues, which animate the humors and give them their respective functions and actions:
     Blood, or the Sanguine humor, is infused with the Attractive Virtue, or force.
     Yellow Bile, or the Choleric humor, is infused with the Digestive Virtue, or force.
     Black Bile, or the Melancholic humor, is infused with the Retentive Virtue, or force.
     Phlegm, or the Phlegmatic humor, is infused with the Expulsive Virtue, or force.
     In the brain, the Vital Force is changed into the Pneuma psychicon, or Psychic Force,  which is the basic form of pneuma for the Psychic Faculty.  You could also call it Nerve Force.  Being closest to the psyche, or indwelling soul in its nature, the Psychic Force also has the attributes of intelligence, awareness, and consciousness.  The Psychic Force is responsible for all sensation and perception, thought and cognition, and movement and response to stimuli.
     In the Generative Faculty, the basic, primal form of pneuma, the Vital Force, is used to spark and germinate a new life. 
     The doctrine of the three forms of pneuma was first developed by Galen as an adjunct to his doctrine of the Four Faculties.  In Hippocrates' day, there was just a general doctrine of pneuma, as the Life Force.


The Three Forms of Ignis 

     Ignis is responsible for all digestion, metabolism and transformation in the organism - in other words, pepsis.  Like pneuma, ignis also has three basic forms in the organism.  Since Air is necessary to combust Fire, ignis is the product of pneuma. 
     Ignis is first combusted in the heart, along with the Vital Force.  There, it assumes its basic, primal form in the organism: the Ignis zoticon, or Innate Heat.  This is the basic body heat emitted by all the organs and tissues of the body due to cellular metabolism.
     The Innate Heat, along with the Vital Force, is carried by the blood to all the organs and tissues of the body to power cellular metabolism.  From there, throughout the organism, these two twin forces, ignis and pneuma, are never far apart.
     In the liver, the Innate Heat is converted into the Metabolic Heat, or Ignis physicon, which powers all pepsis in the Natural Faculty.  Together with the Natural Force, the Metabolic Heat generates the Four Humors.  The Metabolic heat cooks or concocts the humors in a process of pepsis, whereas the Natural Force gives the humors their functions and actions.
     Some say that there is another Fire in the stomach and duodenum called the Digestive Fire, or Ignis gastricon, which cooks or concocts the raw food juices into chyle.  Then, the chyle is sent to the liver to be processed into the Four Humors.  But others attribute the digestive power of these organs to the caustic, Choleric secretions they produce. 
     In the brain, the Innate Heat is converted into the Psychic Heat, or Ignis psychicon, which powers all psychic pepsis, or the digestion, assimilation and processing of thoughts, ideas and experiences.  The Psychic Faculty is the coldest in temperament of all the faculties, so the Psychic Heat is more subtle and latent than blatant or obvious.  Nevertheless, the Psychic Heat, being a Fire principle, is highly developed in those of a fiery Choleric temperament, who have a penetrating insight and a great ability to distill the essential meaning and significance of various thoughts, ideas and experiences. 
     In the Generative Faculty, the basic, primal form of ignis, the Innate Heat, is used as the catalyst to spark a new life.