Pope John XXIII
Mater et Magistra §40
Mater et Magistra: On Christianity and Social Progress
40 The second point which We consider basic in the encyclical is his teaching that man's aim must be to achieve in social justice a national and international juridical order, with its network of public and private institutions, in which all economic activity can be conducted not merely for private gain but also in the interests of the common good.
Source: Mater et Magistra (Vatican.va)