This is taken from a TV programme. It's from a BBC TV series called The Beauty of Diagrams.
The blue squares on the left picture are actually the same colour as the yellow squares on the right hand picture. They are both grey.
(use the pipette tool to sample the colour in Photoshop if you don't believe it).
Edit: I cut around the squares in question and removed the colour from the rest of the picture. I didn't alter the colour in any way:
As the researcher in the programme said, colour doesn't actually exist except within the mind.