"Monday is yellow; Tuesday is quite a deep red; Wednesday is sort of a grass green; Thursday is a much darker green but still quite bright; Friday has always confused me, it's either a very dark purple, blue or grey; Saturday is white; and Sunday is sort of a light peach colour. For anyone who doesn't understand what's happening here, I have a neurological condition called synesthesia which means that I 'see' words in colours."
Winner of the 1965 Nobel Prize in Physics. Feynman had colored letters and numbers.
"When I see equations, I see the letters in colors “ I don't know why. As I'm talking, I see vague pictures of Bessel functions from Jahnke and Emde's book, with light-tan j's, slightly violet-bluish n's, and dark brown x's flying around. And I wonder what the hell it must look like to the students."
Feynman, Richard. 1988. What Do You Care What Other People Think? New York: Norton. P. 59.
"Tenberken had impaired vision almost from birth, but was able to make out faces and landscapes until she was 12. As a child in Germany, she had a particular predilection for colours, and loved painting, and when she was no longer able to decipher shapes and forms she could still use colours to identify objects. Tenberken has, indeed an intense synaesthesia.
"'As far back as I can remember,' she writes, 'numbers and words have instantly triggered colours in me ... number four, for example [is] gold. Five is light green. Nine is vermillion... Days of week, as well as months, have their colours, too.' Her synaesthesia has persisted and been intensified, it seems, by her blindness" [from http://www.fortunecity.com/emachines/e11/86/blind.html].
Rush confesses to a kind of synesthesia, where two senses cross wires. In his case, days of the week are linked to discrete colours: "Friday is dark maroon, a type of sienna, and Saturday is definitely white. Monday is a cool blue." He links the attribute to his Brisbane childhood. "Since I was seven, when I first learnt counting, numbers had specific colours. My kids [Angelica, 14, and James, 11] say, 'Dad you're not abnormal, you're not different – you're just crazy.'"
(See: Campbell, Andrew. 2007. Dr H.V. Evatt “ Part One: A question of sanity. National Observer (Melbourne); No. 73; Winter: 25-39. Also, Crockett, Peter. 1993. Evatt: A Life. Melbourne: Oxford University Press.)