(by which I refer to the discussion about whether colors are objective realities or ideal qualia, not the disagreements that sometimes arise between the functionally illiterate factions who prefer their imaginations to be colored with dyestuffs rather than fanciful ideas).
Physicist Erwin Schroedinger wrote: “The sensation of color cannot be accounted for by the physicist’s objective picture of light-waves.” – But it certainly cannot be accounted for without it. And that is the mistake of idealism. It wants to reduce everything to thought – but “red” is not a sublime thought and neither is it a mere mundane “material reality”. In fact it is almost certainly both at the same time and both objectively real and subjectively ideal. A rose carries its (objective) “redness” in the pigments that are part of its material reality, the human brain sees the (subjective) “redness” of the rose by interpreting electrical impulses induced by the impingement of real photons within a particular range of energies (frequency) on the photosensitive nerve cells in the retina. There is a continuous and very real connection between the rose and the brain. Realism (of the materialist variety) can account for all of that – idealism cannot (except by calling reality an illusion). Where realism struggles is at the point of explaining how the brain interprets what the “redness” of the rose means. But realism strives (against all the barriers of complexity and emergence) to find an explanation – idealism simply imposes an additional (undetectable) layer of “reality” – it says there are these metaphysical “things” called qualia that just sit around in anonymous unreality waiting for a rose and a human brain to make contact and then, hey presto, “redness” suddenly leaps into action miraculously imposing its ideality on the real world. And, as if this first imposture were not enough, ideality then tries to claim supremacy by suggesting that such “ideal forms” are the foundation of the real world. But reality is entirely unconvinced and proves the point by switching off the lights whereupon the “redness” vanishes, but the rose and the brain are still there. Absent the physicists light-waves (or particles – it makes no difference), the “quale” is, if it is anything at all, completely impotent. 1-0 to naturally pigmented reality I think.