When we survey our lives and efforts we soon observe that almost the whole of our actions and desires are bound up with the existence of other human beings. We notice that whole nature resembles that of social animals. We eat food that others have produced, wear clothes that other have made, live in houses that others have built. The greater part of our knowledge and beliefs has been passed on to us by other people though the medium of a language which others have created. Without language and mental capacity we would have been poor indeed comparable to higher animals.