hey jens,
where on earth do you find this information
its a very interesting concept and one i would normally steer clear of, except that i know that this would have played a significant part in the thinking of the day.
however, 'The number seven is of great cosmological significance' makes me want to start burning josticks
i think these seven colours must have been of great importance of the time, enough for jahangir to make an issue of it.
fascinating stuff!