Quadragesimo Anno §69

⁶⁹ It is obvious that, as in the case of ownership, so in the case of work, especially work hired out to others, there is a social aspect also to be considered in addition to the personal or individual aspect. For man's productive effort cannot yield its fruits unless a truly social and organic body exists, unless a social and juridical order watches over the exercise of work, unless the various occupations, being interdependent, cooperate with and mutually complete one another, and, what is still more important, unless mind, material things, and work combine and form as it were a single whole. Therefore, where the social and individual nature of work is neglected, it will be impossible to evaluate work justly and pay it according to justice.