One of the reasons I mentioned colors is that there is shade, there is hue, there is tone, etc… If we take something obvious like light blue to royal blue to navy blue, that could be one kind of pain, and then there could be a yellow kind of pain or a red kind of pain, etc… Pain is a qualitative phenomenon, and upsets some people more than others, depending on what kind of pain it is. I know I’ve dismissed some pain of my own because I knew what caused it, but if I don’t know what it is, it’s a lot worse.