Brain versus Mind By Logic,A Historically Irresolvable Debate
As computer and neuroscience technology progresses, the perceived role of the human brain grows ever more complex and seemingly more determinant as to what makes a person, a self. Research and development projects in both the fields of neuroscience and artificial intelligence add fire to the Mind versus Brain debate. Are the biochemical mechanics of the brain sufficient explanation for human behavior, or is there a “mind”, distinct from the brain, which harbors free will? In other words, are human thoughts and conscious actions[1] entirely based on science or on purposive cause, calling for unscientific philosophy and/or religion? Whether there is a teleological explanation[2] for human behavior and brain activity centers around the issue of determinism. A purely mechanical explanation is intrinsically deterministic, whereas a teleological explanation leaves room for free will. Because the Mind versus Brain debate rests on whether there is free will, and because neither a purely mechanical nor a teleological explanation is logically defensible to a satisfactory extent, the teleological debate concerning human behavior and brain activity is logically irresolvable.
To understand fully teleological and purely mechanical explanations of human behavior and brain activity, it is first necessary to understand the fundamental biochemistry of brain function. Although the brain is the most complex and least understood organ of the human body, its functionally essential constituent is the neuron, which exists in clusters called ganglia.[3] A neuron, or an excitable nerve cell, transfers within the brain an electrochemical (or sometimes a purely electrical) signal to other neurons. This signal can be either excitatory or inhibitory, depending on how a receiving neuron chemically reacts to the signal.[4] A neuron is excited when it receives a signal and its interior and exterior ion concentrations change, allowing for passage of the signal. At rest, or when not excited, the cell has a central shaft, an axon, whose interior is 70mv (millivolts) negative with respect to its exterior.[5] This polarization is due to a transmembrane ion gradient; the exterior medium of the neuron is ten times richer in sodium ions ( ) than the interior, and the interior is ten times richer in potassium ions ( ).[6] When the neuron is excited, axon permeability to increases and a wave of voltage passes through the axon like a flame along a firecracker fuse. When the voltage, the electrical signal, reaches the posterior end of the neuron, it triggers the release of chemicals called neurotransmitters across a physical gap, known as a synapse, between the neuron and another “postsynaptic” neuron.[7] That is how signals pass between neurons in the human brain. As to how signals originate, the cell body is believed to generate an electrical impulse, by means unknown.[8] Also unclear is how...
