Red is a Concept

Categories are "part of our experience". "They are the structures that differentiate aspects of our experience into discernable kinds…the formation and use of categories is the stuff of experience."

"What we call concepts are neural structures that allow us to mentally characterize our categories and reason about them."

"The question of what we take to be real and the question of how we reason are inextricably linked. Our categories of things in the world determine what we take to be real: trees, rocks, animals, people, buildings, and so on. Our concepts determine how we reason about those categories. In order to function realistically in the world, our categories and our forms of reason must "work" very well together;"

In an attempt to enlighten the reader as to the nature of metaphor theory the author explains in some detail three kinds of concepts?-color concepts, basic-level concepts, and spatial level concepts. In the book "Philosophy in the Flesh" the authors explain color perception in some detail in order to exemplify the meaning of ?'concept'. I will give a short rendition of color perception. For more detail of color perception one might examine: http://www.firelily.com/opinions/color.html

"Our experience of color is created by a combination of four factors: wavelengths of reflected light, lighting conditions, and two aspects of our bodies: (1) the three kinds of color cones in our retinas, which absorb light of long, medium, and short wavelengths, and (2) the complex neural circuitry connected to those cones."

One physical property of the surface of the object matters for color: its reflectance (the percentage of high-, medium- and low-frequency light that the object reflects). The actual wavelength reflected by the object do not remain constant it depends upon ambient light, yet the color remains relatively constant. "Color, then, is not just the perception of wavelength; color constancy depends on the brain's ability to compensate for variations in the light source."

Visible light is electromagnetic radiation like radio waves within a certain frequency spectrum. When the electromagnetic radiation impinges on the cones in our retina we perceive color. Color perception is the result of four interacting factors: "lighting conditions, wavelengths of electromagnetic radiation, color cones, and neural processing."

Colors are not objective nor are they purely subjective. "Color is created jointly by our biology and the world, not by our culture." Color results from the interaction of biology and the world. "We have the color concepts we do because the physical limitations constraining evolution gave evolutionary advantages to beings with a color system that enabled them to function well in crucial respects."

A nation has an infrastructure consisting of roads, bridges, rail lines, etc. The brain has mental spaces containing experiences and in these mental spaces there are infrastructure containing categories, concepts, inferences, etc. This is my understanding of the material I have studied in "Philosophy in the Flesh".