Color does exist but not all the colors we know are real. Pink and purple are not real colors in nature it is just our brains playing tricks on us. Our eyes have 3 cones: Blue, Red, and Green.
When it comes to digital and printer ink there are 4 colors that makeup all the colors we see on screens and when we print images. These colors are Cyan, Magenta, Yellow, and black. How light reflects off of things and into our eyes is very important too. All I can say is I love seeing color and I'm thankful for my color cones.