Central features of studies on Caste

This article on Sulekha says:

[B]ut there can be no doubt that for the past thousand years at least the caste system has been a great nightmare for the majority of our people and continues to be a great bane of hindu society as well as hinduism today.

When you write this article on the caste system, I do want you very much to make clear where your certainty regarding the nature of the caste system and its baneful impact both on the hindu and the indian society comes from. There is a reason for this request. For some time, I too thought that the ‘indian caste system’ was an abomination. In order to find out where it came from, the nature of its foundations, and the causes for its continued reproduction, I started reading and researching into the question. Normally, research renders the questions sharper, but in this case the subject became vaguer! The more I read, the more confusing it all became: everyone seemed to be against the caste system (with a few exceptions) but no one seemed to know what it was! While each had very clear moral opinions on the subject, none had any clear understanding of what they were for/against. Consequently, my request: in your article, please (1) do not assume that the caste system is an evil, but show that it is; (2) do not just say it is obvious that it is a bane, but demonstrate it;  (3) do not just affirm that ‘the dalits’ are victims of an immoral and unjust social organisation, but show how and why they are that. So far, I have not been able to prove any of the above claims scientifically (or even unscientifically). Everyone seems to assume it, and the (literally) thousands of books and articles I have read on this score fail miserably in even saying what ‘the caste system’ is, leave alone prove that it is the cause of many social and cultural ills in our culture and society. May I look forward to something that at least provides me with a semblance of a proof?