EthnoPhysics begins by sorting experience into various classes of sensation. The full gamut of human perception is wildly varied, some phenomena forever dancing beyond the grasp of language and mathematics. But even a rudimenary account can be very valuable. So let’s start crudely dividing perceptions into a handful of categories. Definitions are fuzzy. There may be gaps and overlaps. But starting from this oversimplification we progressively add more detail and refinement until we can ultimately communicate with precision and accuracy about our perceptions.
Any vision, sight or ocular experience that could loosely be described as grayish is called an achromatic visual sensation. Any sight that could be roughly described as reddish or greenish is called an organic chromatic sensation. And any image that could be described as yellowish or bluish is called an inorganic chromatic visual sensation.
Strong feelings that are so hot or cold that they are hazardous are called dangerous thermal sensations. Warm or cool feelings that happen during routine human activity are called safe thermal sensations.
Any tactile or auditory perception associated with a sense of touch, pressure, hearing or sound is called a somatic sensation.
Flavors or gustatory perceptions that are produced when a substance in the mouth reacts with nerves of the tongue and palate are called taste sensations. We specifically consider sweet, sour and salty flavors. But bitter, pungent and metallic tastes are other well-known examples from among hundreds of distinctly recognizable flavors.
Smells, odors and olfactory perceptions. Balance and related kinesthetic senses. Animalistic perceptions like echo-location or sensitivity to the Earth's magnetic field. Telepathy, clairvoyance and paranormal abilities. A sense of humor. An eye for beauty. Feeling the weight of injustice. Miracles, memories, hallucinations and dreams. The look of love …
Next we make some assumptions. The first hypothesis is that physics and chemistry are based on describing just nine distinct classes of sensation, i.e. the ones with icons in the table above. Other genres of description are certainly possible, and any system is discretionary. For example, different cultures may use different color terms to describe the same visual stimulus. Moreover, any categorical system also introduces a bias by oversimplifying and truncating the number of primary distinctions. For example, the sensation of orangeness cannot be fundamentally grasped by a system that only recognizes yellow and red as elementary sensations.
Nonetheless, it is possible to understand a lot of physics and chemistry using just nine categories. Less than nine leads to oversimplification, loss of detail and ultimately a loss of usefulness. More than nine allows for more descriptive subtlety, with the cost of more messy complexity. So we use nine classes of sensation along with binary descriptions for simple accounting and practical reporting.