Functionalism is one of the many mental theories based on the philosophical premise that every feeling, emotion, or thought in the mind is associated solely with the idea that each has a function. Essentially, it is a cause and effect idea in which each outside stimuli corresponds to a mental state which causes a reaction. The base principles of the theory rely solely on the understanding of how the brain functions to outside stimulation, essentially how the “software” in the human mind is organized.
According to the theory, mental states are designed on multiple levels which manifest themselves into various systems and organizational structures not dissimilar to computers. The brain is a physical device that uses neural substrate to perform computations based on the input from the world, while computers are physical devices which use electronic substrate to perform computations based on the input from users. This is the core philosophy, causing many theorists to discount the argument, stating it does not fully explain the complex functions of the human brain.
The theory of functionalism brings about the concept that a computer itself may have a certain level of mental state. This is brought about by the idea of multiple realizability; the concept that mental states are simply a functional role, thereby anything, not just a higher-level cognitive system, should have a functional mind. For example, a knob on a faucet can be made from any material; as long as it performs its function of controlling water flow, it is said to have a functional role and thereby a mental state based on the theory.
There are many different types of functionalism: machine, psycho-functionalism, analytic, or homuncular. Each of these concepts attempts to derive some sort of philosophical truth about the brain and its functions. Most of the ideas stemmed from research conducted in the field of functionalism psychology throughout the 1960s and 1970s.
Many philosophers argue whether an association between functionalism and physicalism, the idea that everything is the sum of physical properties, exists. Some claim that functionalism in its root form, disproves physicalism, while other argue that the concepts can coexist side-by-side. Most of the arguments for divergence relies on the concept that functionalism has no interest in what physically exists, but only what the state of mind means.
One of the great theories in functionalism is the “China brain” concept. This argument, postulated in 1980 by philosopher Ned Block, addressed the concept of what would happen if the entire nation of China would begin to operate as a brain. Essentially, each person in thee country would take the job of a neuron and fulfill the roles in a collective manner. According to functionalism, the collective body, as long as people continued operating in their roles, would be considered a single mind.
