Pacem in Terris

Finally, it is opportune to point out that the right to own private property entails a social obligation as well. ^{19Cf. ibid., p. 430; TPS v. 7, no. 4, p. 318.}

Men are by nature social, and consequently they have the right to meet together and to form associations with their fellows. They have the right to confer on such associations the type of organization which they consider best calculated to achieve their objectives. They have also the right to exercise their own initiative and act on their own responsibility within these associations for the attainment of the desired results^{20Cf. Leo XIII's encyclical letter Rerum novarum, Acta Leonis XIII, XI, 1891, pp. 134-142; Pius XI's encyclical letter Quadragesimo anno, AAS 23 (1931) 199-200; and Pius XII's encyclical letter Sertum laetitiae, AAS 31 (1939) 635-644.}.