I think I'm understanding what you're saying, I just disagree :)
> They show up as being a color in the picture not because of their inherent qualities, but because of what wavelengths of light they do or do not absorb.
The intrinsic/perceived duality that you're setting up here isn't related to what a spectrum is. What's fundamental for spectrums is that they're expansive: whatever the measured quality is, all such things map to somewhere on a single dimension which is the spectrum.
Color has been overused. Let's consider a mass spectrometer. It gives an electric charge to a sample, hurls it through a perpendicular magnetic field, and depending on the masses of the sample (or its components, supposing the ionization process broke it up), inertia causes spatial separation. Not-very-massive over here, and quite-massive over there. This is a spectrum because all masses have a place on it (nevermind that you might not actually be able to build a large enough spectrometer for some masses).
Or to use a mathematical example, if you exclude the interval [0,1] from the real number line, what you get is no longer a continuum, and mappings of things onto it are no longer a spectrum.
It may be a misconception that all political perspectives exist on a left/right axis, but when people talk about the political spectrum they're invoking a simplification under which all people do map to some point or another on that line.
As far as I'm aware it's only the autism spectrum that doesn't work this way.
> They show up as being a color in the picture not because of their inherent qualities, but because of what wavelengths of light they do or do not absorb.
The intrinsic/perceived duality that you're setting up here isn't related to what a spectrum is. What's fundamental for spectrums is that they're expansive: whatever the measured quality is, all such things map to somewhere on a single dimension which is the spectrum.
Color has been overused. Let's consider a mass spectrometer. It gives an electric charge to a sample, hurls it through a perpendicular magnetic field, and depending on the masses of the sample (or its components, supposing the ionization process broke it up), inertia causes spatial separation. Not-very-massive over here, and quite-massive over there. This is a spectrum because all masses have a place on it (nevermind that you might not actually be able to build a large enough spectrometer for some masses).
Or to use a mathematical example, if you exclude the interval [0,1] from the real number line, what you get is no longer a continuum, and mappings of things onto it are no longer a spectrum.
It may be a misconception that all political perspectives exist on a left/right axis, but when people talk about the political spectrum they're invoking a simplification under which all people do map to some point or another on that line.
As far as I'm aware it's only the autism spectrum that doesn't work this way.