Socks again

When I set my son the task of choosing 4 balls of sock yarn for himself I expected varying shades of pure black. That's what I picked out for his first three pairs. Imagine my surprise when he then chose a bright red, one with bright blues and most surprising of all this rainbow yarn. I was thrilled to bits. We'd left the Black Death behind. Then I remembered. He is colour blind. Not just a little bit but quite an usual form that put an end to after, until that point, a very good application and subsequent interviews, to be selected for the RAF's officer training. Heaven knows what he sees when looks at his rainbow socks but it sure isn't what I see.
Cute!