None of this is true, as demonstrated by pain.
Because that’s what our science has determined. Material objects just reflect light at various wavelengths, as determined by the arrangement of electrons on their surface. These are not colours. Colours are a type of visual experience, no different in principle to pain, that occur when the appropriate areas of the brain are active. This explains how hallucinations, synaesthesia, and differences in colour perception are possible.
But don’t just take my word for it. From A Problem with Color:
One of the major problems with color has to do with fitting what we seem to know about colors into what science (not only physics but the science of color vision) tells us about physical bodies and their qualities. It is this problem that historically has led the major physicists who have thought about color, to hold the view that physical objects do not actually have the colors we ordinarily and naturally take objects to possess. Oceans and skies are not blue in the way that we naively think, nor are apples red (nor green). Colors of that kind, it is believed, have no place in the physical account of the world that has developed from the sixteenth century to this century.
Not only does the scientific mainstream tradition conflict with the common-sense understanding of color in this way, but as well, the scientific tradition contains a very counter-intuitive conception of color. There is, to illustrate, the celebrated remark by David Hume:
“Sounds, colors, heat and cold, according to modern philosophy are not qualities in objects, but perceptions in the mind.” (Hume 1738: Bk III, part I, Sect. 1 [1911: 177]; Bk I, IV, IV [1911: 216])
Physicists who have subscribed to this doctrine include the luminaries: Galileo, Boyle, Descartes, Newton, Thomas Young, Maxwell and Hermann von Helmholtz. Maxwell, for example, wrote:
“It seems almost a truism to say that color is a sensation; and yet Young, by honestly recognizing this elementary truth, established the first consistent theory of color.” (Maxwell 1871: 13 [1970: 75])
This combination of eliminativism—the view that physical objects do not have colors, at least in a crucial sense—and subjectivism—the view that color is a subjective quality—is not merely of historical interest. It is held by many contemporary experts and authorities on color, e.g., Zeki 1983, Land 1983, and Kuehni 1997. Palmer, a leading psychologist and cognitive scientist, writes:
“People universally believe that objects look colored because they are colored, just as we experience them. The sky looks blue because it is blue, grass looks green because it is green, and blood looks red because it is red. As surprising as it may seem, these beliefs are fundamentally mistaken. Neither objects nor lights are actually “colored” in anything like the way we experience them. Rather, color is a psychological property of our visual experiences when we look at objects and lights, not a physical property of those objects or lights. The colors we see are based on physical properties of objects and lights that cause us to see them as colored, to be sure, but these physical properties are different in important ways from the colors we perceive.” (Palmer 1999: 95)
And from Neural representations of perceptual color experience in the human ventral visual pathway:
Color is in the perceiver, not the physical stimulus. This distinction is critical for understanding neural representations, which must transition from a representation of a physical retinal image to a mental construct for what we see. Here, we dissociated the physical stimulus from the color seen by using an approach that causes changes in color without altering the light stimulus.
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Color is a perceptual construct that arises from neural processing in hierarchically organized cortical visual areas.
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We now know that the colors we see follow from biological neural representations generated by light, but light itself carries no color.