References to color blindness

[Dr. M.F. Tritsch]

I am not an indologist, but I am hoping members of the indology 
list will help me with an interesting problem of 
medical history. Reading a book by H. v. Glasenapp on Shankara 
(Der Stufenweg zum Goettlichen), I discovered a reference to color 
blindness as a metaphor for maayaa. He says maayaa 
is like when someone sees the moon double or MISTAKES SOMETHING
WHITE FOR YELLOW. 

v. Glasenapp does not give the source - can anyone help here? And are 
there other old texts from India which refer to color blindness in 
some way? This would especially interest me!

The example with white and yellow is very unusual, as this kind of 
color blindness is rare (more common is red and green) - but perhaps 
people using these colors a lot (religious garments, etc.) 
notice it more. In the ancient literature of the west, there is 
very little mention of color blindness.

Thanks in advance for any help!

Mark Tritsch

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DR. MARK F. TRITSCH      (Tel/Fax: +49 611 691497)

Institut fuer Zoologie III
Johannes Gutenberg Universitaet
55099 Mainz
Germany

Schnappschuss internationale Forschungsnachrichten
Breslauer Strasse 14 b
65203 Wiesbaden
Germany

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