The Physical Body is the outer most expression of the Human Being, the densest of the three bodies. It is the material vehicle through which the material world is experienced.
This is what anchors all the other components of the Human Being into this reality.
An analogous system would be computer hardware. That is, the physical components of a computer system, including the BIOS/Firmware.
BIOS (Basic Input Output System) runs and controls the hardware components in a computer system, such as the CPU, memory, storage devices and also interfaces with other peripherals.
The nervous system of the Human Body is equivalent to computer BIOS, although it is orders of magnitude more sophisticated. It controls the hardware components of the Physical Body, such as the brain, the heart, the lungs, the reflexes, physical senses and many other systems and functions.
The endocrine system is also deeply integrated into control and signalling functionality.
The Human Physical Body is the biological instrument that runs the program, the algorithm of the Human Psyche.
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