With all the wisdom in forming these four castes, there is a selfishness shown on the part of the high classes, as has been always the case with the human race; and that has been a great hindrance to the progress of Hindus in general, for every chance of progress was shut out for the lower classes. Their only consolation was to reincarnate and be born in a higher class. If not, there was no other way. This is the chief reason which gave the doctrine of reincarnation importance in the Hindu race.