Economically the world was as different from our own as it was geographically.  Money, if not unknown, was for the most part unused.  It had drifted eastwards, in the latter days of the Roman Empire, to purchase silks and spices; and it had never returned.  From the days of Diocletian, society had been thrown back on an economy in kind.  Taxes took the form either of payments of personal service or of quotas of produce:  rents were paid either in labour or in food.  The presence of money means a richly articulated society, infinitely differentiated by division of labour, and infinitely connected by a consequent nexus of exchange.  The society of the Middle Ages was not richly articulated.  There were merchants and artisans in the towns; but the great bulk of the population lived in country villages, and gained subsistence directly from the soil.  Each village was practically self-sufficing; at the most it imported commodities like iron and salt; for the rest, it drew on itself and its own resources.  This produced at once a great uniformity and a great isolation.  There was a great uniformity, because most men lived the same grey, quiet life of agriculture.  The peasantry of Europe, in these days when most men were peasants, lived in the same way, under the same custom of the manor, from Berwick to Carcassonne, and from Carcassonne to Magdeburg.  But there was also a great isolation.  Men were tied to their manors; and the men of King’s Ripton could even talk of the ‘nation’ of their village.  If they were not tied by conditions of status and the legal rights of their lord, they were still tied, none the less, by the want of any alternative life.  There were towns indeed; but towns were themselves very largely agricultural—­the homes of summa rusticitas—­and what industry and commerce they practised was the perquisite and prerogative of local guilds.  Custom was king of all things, and custom had assorted men in compartments in which they generally stayed.  The kaleidoscopic coming and going of a society based on monetary exchanges—­its speedy riches and speedy bankruptcies, its embarrassment of alternative careers all open to talents—­these were unthought and undreamed of.  The same uniformity and the same isolation marked also, if in a less degree, the knightly class which followed the profession of arms.  A common feudal system, if we can call that a system which was essentially unsystematic, reigned over the whole of Western Europe, and, when Western Europe went crusading into Syria, established itself in Syria.  Historians have tried to establish distinctions between the feudalism of one country and that of another—­between the feudalism of England, for instance, and that of France.  It is generally held nowadays that they have failed to establish the distinction.  A fief in England was uniform with a fief in France, as a manor in one country was uniform with manors in other countries, and a town in one country with towns in others.  ’One cannot establish a line of