[juwo]

It is my observation - I too studied in India. It is common knowledge that brahmins (caste) as a group are more intelligent than the average population. For example, They have made up the bulk of Nobel laureates from India.

My room mate was from the untouchable caste (translation for Americans). He was super intelligent too - managed to leave the country and got 2 post graduate degrees in the USA, trained himself to run marathons.

regarding your comment on hereditary occupations, please read this article

And no, I am not a brahmin.

http://news.bbc.co.uk/2/hi/south_asia/2231011.stm

"In the dead of the night, when the city of six million goes to sleep, groups of jobless low-caste Hindus, known as Dalits, eke out a living by removing human excrement from pits in the poorer neighbourhoods of the city."