I find it interesting that the last terms in the hierarchy are pastels. If you have one basic pastel, it's grey. Two: you have grey and pink. Three: grey, pink,

I find it interesting that the last terms in the hierarchy are pastels. If you have one basic pastel, it's grey. Two: you have grey and pink. Three: grey, pink, and robin's egg blue. Pastel brown, purple, and green are easy for the human eye to distinguish (yellow and orange less so), but they never make the cut. Actually, I speaking a bit off the cuff. I don't recall where grey is in the hierarchy -- it's towards the end -- but the last two are pink and pastel blue.