(March 29, 2018 at 3:52 pm)Khemikal Wrote:(March 29, 2018 at 3:48 pm)vulcanlogician Wrote: Let's stick with color then. Outside of the mind there is no such thing as "blue". There are light waves. We can measure the wavelength of the light (in the same way we can measure temperature) and say "that is what the mind interprets as blue" but blueness exists only as an idea.
Sunflowers disagree...all plants disagree. They respond to a narrow wavelength and reflect the rest. Auxin, btw. It's a photophobic growth hormone. (one of) Their version(s) of a mechanoreceptor..except that it senses light. Cool shit, huh.
Blueness may be "only an idea"..lets run with it. - why would that matter to the argument..if ideas have mass and occupy space anyway?
Sunflowers respond to wavelengths of lights. Wavelength is an actual primary quality of waves of light. The idea of light doesn't have wavelength (so to speak)... it has blueness. Blueness doesn't exist outside of the realm of ideas. Therefore ideas are essentially different than material things. There is a causal relation between material and ideas but not an essential similarity.
