Vital heat
Encyclopedia
Vital heat, also called innate or natural heat, or calidum innatum, is a term that has generally referred to the heat produced within the body, usually the heat produced by the heart
and the circulatory system
.
According to Ancient Greek
physicians, vital heat was produced by the heart
, maintained by the pneuma
(air, breath, spirit
or soul
), and circulated throughout the body by blood vessels, which were thought to be intact tubes using blood to transmit heat. Aristotle
supported this argument by showing that when the heart is made cold compared to other organs, the individual dies. He believed that the heat produced in the heart caused blood to react in a similar way to boiling, expanding out through the blood vessels with every beat. This extreme heat, according to him, can lead to a self-consuming flame
if it is not cooled by air from the lungs.
Galen
wrote in On the Usefulness of the Parts of the Body (170
): "The heart is, as it were, the hearthstone and source of the innate heat by which the animal is governed." In the 11th century, Avicenna
agreed with this notion, stating that the heart produced breath, the "vital power or innate heat" within the body, in his Canon of Medicine.
Later, the term innate heat was attributed to friction caused by the motion of blood through arteries, as evidenced by the Cyclopaedia (1728):
Heart
The heart is a myogenic muscular organ found in all animals with a circulatory system , that is responsible for pumping blood throughout the blood vessels by repeated, rhythmic contractions...
and the circulatory system
Circulatory system
The circulatory system is an organ system that passes nutrients , gases, hormones, blood cells, etc...
.
According to Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
physicians, vital heat was produced by the heart
Heart
The heart is a myogenic muscular organ found in all animals with a circulatory system , that is responsible for pumping blood throughout the blood vessels by repeated, rhythmic contractions...
, maintained by the pneuma
Pneuma
Pneuma is an ancient Greek word for "breath," and in a religious context for "spirit" or "soul." It has various technical meanings for medical writers and philosophers of classical antiquity, particularly in regard to physiology, and is also used in Greek translations of the Hebrew Bible and in...
(air, breath, spirit
Spirit
The English word spirit has many differing meanings and connotations, most of them relating to a non-corporeal substance contrasted with the material body.The spirit of a living thing usually refers to or explains its consciousness.The notions of a person's "spirit" and "soul" often also overlap,...
or soul
Soul
A soul in certain spiritual, philosophical, and psychological traditions is the incorporeal essence of a person or living thing or object. Many philosophical and spiritual systems teach that humans have souls, and others teach that all living things and even inanimate objects have souls. The...
), and circulated throughout the body by blood vessels, which were thought to be intact tubes using blood to transmit heat. Aristotle
Aristotle
Aristotle was a Greek philosopher and polymath, a student of Plato and teacher of Alexander the Great. His writings cover many subjects, including physics, metaphysics, poetry, theater, music, logic, rhetoric, linguistics, politics, government, ethics, biology, and zoology...
supported this argument by showing that when the heart is made cold compared to other organs, the individual dies. He believed that the heat produced in the heart caused blood to react in a similar way to boiling, expanding out through the blood vessels with every beat. This extreme heat, according to him, can lead to a self-consuming flame
Spontaneous human combustion
Spontaneous human combustion describes reported cases of the burning of a living human body without an apparent external source of ignition...
if it is not cooled by air from the lungs.
Galen
Galen
Aelius Galenus or Claudius Galenus , better known as Galen of Pergamon , was a prominent Roman physician, surgeon and philosopher...
wrote in On the Usefulness of the Parts of the Body (170
170
Year 170 was a common year starting on Sunday of the Julian calendar. At the time, it was known as the Year of the Consulship of Clarus and Cornelius...
): "The heart is, as it were, the hearthstone and source of the innate heat by which the animal is governed." In the 11th century, Avicenna
Avicenna
Abū ʿAlī al-Ḥusayn ibn ʿAbd Allāh ibn Sīnā , commonly known as Ibn Sīnā or by his Latinized name Avicenna, was a Persian polymath, who wrote almost 450 treatises on a wide range of subjects, of which around 240 have survived...
agreed with this notion, stating that the heart produced breath, the "vital power or innate heat" within the body, in his Canon of Medicine.
Later, the term innate heat was attributed to friction caused by the motion of blood through arteries, as evidenced by the Cyclopaedia (1728):
- "For 'tis hence we know, that this innate Heat is no more than the Attrition of the Parts of the Blood; occasion'd by its circulatory Motion, especially in the Arteries;"