How did Thomas Hobbes explain sensations and thoughts?

Thomas Hobbes, a mechanical materialist, explained sensations and thoughts as the results of matter in motion. He rejected the traditional view that objects transmit "sensible forms" to the senses; instead, he argued that all knowledge arises from sense experiences caused by the physical action of external bodies on our sense organs.1234

In his theory of perception, physical objects stimulate the sense organs and nerves, creating internal motions that are transmitted to the brain. This process results in a "phantasm," or sense-image, within the mind. Because Hobbes believed that only material things are real, he maintained that these mental phenomena—including thoughts and the "passions and perturbations of the mind"—are simply the effects of these internal physical motions. Consequently, he dispensed with the need to explain the qualities of a sense-image through the qualities of the perceived object, relying entirely on the mechanics of the nervous system and sensory membranes to account for human experience.142