Men clearly do not find it easy to do without satisfaction of this tendency to aggression that is in them; when deprived of satisfaction of it they are ill at ease. There is an advantage, not to be undervalued, in the existence of smaller communities, through which the aggressive instinct can find an outlet in enmity towards those outside the group. It is always possible to unite considerable numbers of men in love towards one another, so long as there are still some remaining as objects for aggressive manifestations. I once interested myself in the peculiar fact that peoples whose territories are adjacent, and are otherwise closely related, are always at feud with and ridiculing each other, as, for instance, the Spaniards and the Portuguese, the North and South Germans, the English and the Scotch, and so on. I gave it the name of ‘narcissism in respect of minor differences’, which does not do much to explain it. One can now see that it is a convenient and relatively harmless form of satisfaction for aggressive tendencies, through which cohesion amongst the members of a group is made easier. The Jewish people, scattered in all directions as they are, have in this way rendered services which deserve recognition to the development of culture in the countries where they settled; but unfortunately not all the massacres of Jews in the Middle Ages sufficed to procure peace and security for their Christian contemporaries. Once the apostle Paul had laid down universal love between all men as the foundation of his Christian community, the inevitable consequence in Christianity was the utmost intolerance towards all who remained outside of it; the Romans, who had not founded their state on love, were not given to lack of religious toleration, although religion was a concern of the state and the state was permeated through and through with it. Neither was it an unaccountable chance that the dream of a German world-dominion evoked a complementary movement towards anti-semitism; and it is quite intelligible that the attempt to establish a new communistic type of culture in Russia should find psychological support in the persecution of the bourgeois. One only wonders, with some concern, however, how the Soviets will manage when they have exterminated their bourgeois entirely.