If you have a one dimensional line, you can use a 1 dimensional value x to represent its position. If you add a second input, y, and instead say that your posit

If you have a one dimensional line, you can use a 1 dimensional value x to represent its position. If you add a second input, y, and instead say that your position on the line is x+y, the line is still one dimensional, even though y changes how the value x is perceived. (Because the point x,y can still be represented with a single value z where z=x+y) There are three colour receptors, so colour is 3 dimensional to us. That the surrounding context shifts where that 3d point falls in the colour space doesn't create more colours, it just shifts the perceived colour around the colour space. In your strawberry example, the gray and red already exist in the 3d colour space. The context did not create these, it just shifted our perception a little off the point in the colour space that the pixel value alone would have placed it. Similarly, if I wear sunglasses, the darkness doesn't add another dimension, it just shifts all the values a bit in a direction that makes them darker. Note: I'm not actually arguing that there are only 3 dimensions of colour (although our three receptors would suggest it), as I don't know enough about it. I'm just pointing out a flaw in your logic.