Exploring Theories of Mind: Monism, Dualism, and Functionalism
Materialist Monism/Physicalism (20th Century Neurobiology)
This theory posits that mental states are neurophysiological brain states. The mind is reduced to or identified with physical things, reducing all reality to the physical level. The human being is a set of cells, and thought processes are explained through physics and chemistry. The mind is like the brain or a set of neurophysiological processes. A memory or idea is merely a physical relationship between neurons and chemicals produced. The brain is a machine.
Criticisms of Reductionism
Critics argue that reductionism cannot explain the qualitative leap of physicochemical thought. If every mental state is reduced to a physical state, they should share the same properties, but neural states are observable while mental states are not. This theory also struggles to account for computer-like mental functions in non-neuronal systems.
Functionalism
Functionalism also reduces mental processes to neurophysiological processes but defines a mental phenomenon or process by its role rather than the material it is made of.
Property Dualism or Emergentism
This theory combines elements of monism and dualism. It suggests that a human being consists of a single substance (natural), but this single substance yields two types of properties: physical and mental. Mental states emerge from physical states but cannot be identified with them because they have different properties. Systematic properties arise from the combination of elements in a system but are not present in the individual elements (e.g., H2O can extinguish fire, but hydrogen and oxygen alone cannot).
Plato
Plato’s anthropological dualism divides the human being into two distinct substances:
- Soul: Spiritual, simple, immortal, divine source of life and knowledge.
- Body: Material, mortal, a prison for the soul.
The body’s desires and needs can enslave the soul, and the soul’s destiny cannot be fulfilled without liberation from the body. Their relationship is accidental, not natural. The divine soul is locked in an imperfect and mortal body. The soul can live without the body, but the body cannot live without a soul. Plato identifies three soul types: rational, irascible, and concupiscible.
Aristotle
Aristotle offers a biological explanation of the human being, distinguishing between living and non-living substances. The soul is the principle that gives life, implying that all living things have souls. The natural world is organized into four realms: inorganic beings, plants, animals, and humans.
- Vegetative Function: Covers basic biological functions like nutrition, growth, and reproduction (plants, animals, and humans).
- Sensory Function: Allows for sensory knowledge and includes bodily desires and animal movement (animals and humans).
- Rational Function: Enables intelligence, understanding, rationality, and scientific knowledge (humans).
For Aristotle, the human being is a body with organs and features suited for life, and the soul is the form that enables the body’s vital functions.
Descartes
Descartes divides human beings into two independent substances: res cogitans (thinking substance) and res extensa (extended substance/body). The thinking substance is the conscious self, immaterial and a free decision-maker, with understanding and will as its functions. The extended substance is the body, with length, width, and depth. Descartes acknowledged the interaction between soul and body, suggesting the pineal gland as the connection point.
Monism
Monistic philosophers argue that the human being is a single material substance, rejecting the existence of a spiritual principle or soul that persists after death.
Democritus
Democritus explains the universe, including human beings, through atomism. Reality is composed of eternal atoms moving in space, colliding to form all beings. Anthropologically, Democritus views the human being as a unique entity composed of body and soul. The soul, responsible for movement and life, consists of spherical and light atoms. These atoms generate heat and move throughout the body, enabling mental and physical functions. Death occurs with the absence of breathing.