And the letters are?
The first time someone showed me a picture like this (at school) and asked me what I saw, I said:
I see a page in a book with red and pink and yellow and light and dark green circles which all put together form a big circle.
I also see the teacher's lap, his blue pants the wallpaper, and somewhere there I was interrupted before I was even halfway in describing what I saw.
I'm not even sure if I started my description with the page in that book.
I do rember that I found the whole exersize a strange and idiotic. Can't the teacher see for himself what's in that book?
Why would I care what's in that book?
It's probably some small childhood trauma that I saved such a picture in my pictures collection.