It took a long time, however, to mitigate that feeling of hostility which seems to have existed in early times between different communities. Even when they condescended to barter with each other they did not forget the difference between the friend and the foe. In the _Senchus Mor_, a book compiled by the old Irish or ‘Brehon’ lawyers, this difference between dealing with a friend and a stranger is rather curiously indicated in considering the rent of land. ‘The three rents,’ says the _Great Book of the Law_, as it is called, ‘are rack rent (or the extreme rent) from a person of a strange tribe, a fair rent from one of the tribe (that is one’s own tribe), and the stipulated rent, which is paid equally by the tribe and the strange tribe.’ Such a distinction is generally recognized in all early communities. In dealing with a man of his own tribe, the individual was held bound in honour not to take any unfair advantage, to take only such a price, to exact only such a value in exchange, as he was legitimately entitled to. It was quite otherwise, however, in dealings with members of other tribes. Then the highest value possible might justly be obtained for any article; so that dealings at markets which consisted of exchanges between different tribes, came to mean a particular sort of trading, where the highest price possible was obtained for anything sold. It is probable that this cast, to a certain extent, a slur upon those who habitually devoted themselves to this kind of trading. Though it was recognized as just to exact as high a price as possible from the stranger, still the person who did so was looked upon to a certain extent as guilty of a disreputable action; viewed, in fact, much in the same light as usurious money-lenders are viewed nowadays. They were people who did not offend against the laws of their times, but who sailed so near the wind as to be tainted, as it were, with fraud. Indeed, our word ‘monger,’ which simply means ‘dealer,’ comes from a root which, in Sanskrit, means ‘to deceive;’ so commerce and cheating seem to have been early united, and we must therefore not be surprised if they are not entirely divorced even in our own time.