How many colors are there?

I’ve been pushing a related but more accessible idea on my friends, or whatever you call people who will mostly listen to you. Stare at a deep red light that does little to stimulate your blue sensors, until they are tired. Then quickly change to a deep blue light, which would normally stimulate your red sensors too. Since they are tired now, you will see a larger blue:red ratio than you have ever seen before. That would be a new color, one which can’t be seen except fleetingly.

That’s a totally cool idea!

I’m not exactly positive on a precise number of colors, but our eyes can see somewhere around 20,000.

I didn’t realise that, but now you mention it, it makes sense. How can something move 1 Planck length in more than 1 Planck time (without it being halfway at some point in between)? It makes nonsense of the idea of quantized space (or time)

Seven. ROY G BIV. According to a Trivial Pursuit question I missed 25 years ago. But I’m not bitter.