8a[http://www.newadvent.org/cathen/12783a.htm]
[The Catholic Encyclopedia]
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Let it be taken for granted that workman and employer should, as a rule, make free agreements, and in particular should agree freely as to wages; nevertheless, there is a dictate of natural justice more imperious and ancient than any bargain between man and man, that remuneration should be sufficient to maintain the wage-earner in reasonable and frugal comfort.
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8b[Leo XIII, Pope, Catholic Church, 1893, Rerum novarum, English translation of encyclical letter of Pope Leo XIII on the condition of the working classes, published by the Vatican, http://www.vatican.va/holy_father/leo_xiii/encyclicals/documents/hf_l-xiii_enc_15051891_rerum-novarum_en.html]
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45. Let the working man and the employer make free agreements, and in particular let them agree freely as to the wages; nevertheless, there underlies a dictate of natural justice more imperious and ancient than any bargain between man and man, namely, that wages ought not to be insufficient to support a frugal and well-behaved wage-earner.
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