The constitution divides our society into different castes, which are determined on the basis of birth. This is totally wrong and unscientific. The society should actually be classified on the basis of qualities and capabilities and actual work done by the individual. In old times, our society was classified into four classes as Brahmin (knowledge based), Kshatriya (power based), Vaishya (wealth based) and Shudra (labour and service based) as per the qualities and work done by the individual. The class of the individual was not determined by his birth. So this system was flexible and scientific. We should adopt this system, of course with modifications which will make it suitable for the present times. There can be sub classes within the classes, which can represent different trades, profession etc. which are now called castes. In this system, the castes will represent the actual work done by the individual and therefore the castes census will represent the actual status and conditions of that trade or profession.