As we have already seen, we cannot sustain the claim that vocations are determined today according to the qualities of individuals and their inclinations or aptitudes. Also untenable is the demand for equal opportunities for all. To take an example: there are a certain number of seats in medical and engineering colleges. For highly specialised and new subjects like nuclear science the seats are very few. When the candidates possessing the same qualifications (or merit) apply for admission to the colleges teaching these subjects only a fixed number are selected. Naturally, it is not practicable to choose all. Would it be right to contend that all candidates, even though equally qualified, who want to do research in a new science like atomic physics, should be given an opportunity? All those who apply for high positions in the government will not be selected for appointment even though they possess more or less same qualifications. The government decides that we need so many doctors in the country, so many scientists, so many specialists and so many officials. In choosing them, a number of candidates are naturally rejected. This system is accepted by all.
It is in the same way as candidates are selected for seats in the colleges or for appointments in the government that a certain percentage of people are thought to be sufficient for the purpose of conducting the rites meant to invoke the heavenly powers for the happiness of mankind - and these few function on a hereditary basis. Not more are needed for such a task since all the other work required for the proper functioning of the society will otherwise suffer. This is the principle on which vocations are divided. People agitate for the application for the principle of equality (a product of French Revolution) to scriptural matters without realising that it has hardly any place even in worldly affairs.
For a general background, please see here