The rent of land, whether paid in labour or in kind, was a customary rent; and in every mediaeval community the landed class was the majority. It was an easy transition from fixed and customary rents to the fixing of just prices for commodities and services. Lay sentiment supported clerical principle. Guilds compelled their members to sell commodities at a level price, and in a spirit of collectivism endeavoured to prevent the making of corners and the practice of undercutting. Governments refused to recognize the 'laws' of demand and supply, and sought, by Statutes of Labourers, to force masters to give, and workman to receive, no more and no less than a 'just' and proper wage. It was not only by the regulation of trade and commerce that the Church sought to penetrate the life of the towns. The friars made their homes in the towns in the thirteenth century; and the activity of the friars--Franciscan and Dominican, Austin and Carmelite--enabled the Church to exercise an influence on municipal life no less far-reaching than that which she sought to exert on the feudal classes. Towns became trustees of property for the use of the mendicant orders; and the orders of Tertiaries, which flourished among them, enabled the townsfolk to attach themselves to religious societies without quitting the pursuits of lay life. A mediaeval town--with its trade and commerce regulated, however imperfectly, by Christian principle; with its town council acting as trustee for religious orders; and with its members attached as Tertiaries to those orders--might be regarded as something of a type of Christian society; and St. Thomas, partly under the influence of these conditions, if partly also under the influence of the Aristotelian philosophy of the [Greek: polis], is led to find in the life of the town the closest approach to the ethics of Christianity.