Men do not become a society by living in physical proximity any more than a man ceases to be a member of his society by living so many miles away from other men.

Secondly similarity in habits and customs, beliefs and thoughts are not enough to constitute men into society.

Things may be passed physically from one to another like bricks. In the same way habits and customs, beliefs and thoughts of one group may be taken over by another group and there may thus appear a similarity between the two.

Culture spreads by diffusion and that is why one finds similarity between various primitive tribes in the matter of their habits and customs, beliefs and thoughts, although they do not live in proximity. But no one could say that because there was this similarity the primitive tribes constituted one society.

This is because similarly in certain things is not enough to constitute a society.

Men constitute a society because they have things which they possess in common.

To have similar thing is totally different from possessing things in common.

And the only way by which men can come to possess things in common with one another is by being in communication with one another. This is merely another way of saying that Society continues to exist by communication indeed in communication.

To make it concrete, it is not enough if men act in a way which agrees with the acts of others. Parallel activity, even if similar, is not sufficient to bind men into a society. This is proved by the fact that the festivals observed by the different Castes amongst the Hindus are the same.

Yet these parallel performances of similar festivals by the different castes have not bound them into one integral whole. For that purpose what is necessary is for a man to share and participate in a common activity so that the same emotions are aroused in him that animate the others.

Making the individual a sharer or partner in the associated activity so that he feels its success as his success, its failure as his failure is the real thing that binds men and makes a society of them.

The Caste System prevents common activity and by preventing common activity it has prevented the Hindus from becoming a society with a unified life and a consciousness of its own being.

SECTION VI, Annihilation of Caste. Vol-I, Dr Babasaheb Ambedkar Writings and Speeches