[Footnote 1:  ’Indigentia istius hominis vel illius non mensurat valorem commutabilium; sed indigentia communis eorum qui inter se commutare possunt,’ Buridan, op. cit., v. 16.  ’Prout communiter venditur in foro,’ Henri de Gand, Quod Lib., xiv. 14; Nider, De Cont.  Merc., ii. 1.]

[Footnote 2:  ‘La Justice dans l’Echange,’ Semaine Sociale de France, 1911, p. 168.]

The writers of the Middle Ages show a very keen perception of the elements which invest an object with the value which is accorded to it by the general estimation.  In Aquinas we find certain elements recognised—­’diversitas loci vel temporis, labor, raritas’—­but it is not until the authors of the fourteenth and fifteenth centuries that we find a systematic treatment of value.[1] First and foremost there is the cost of production of the article, especially the wages of all those who helped to produce it.  Langenstein lays down that every one can determine for himself the just price of the wares he has to sell by reckoning what he needs to support himself in the status which he occupies.[2] According to the Catholic Encyclopaedia,[3] the just price of an article included enough to pay fair wages to the worker—­that is, enough to enable him to maintain the standard of living of his class.  This, though not stated in so many words by Aquinas, was probably assumed by him as too obvious to need repetition.[4] ‘The cost of production of manufactured products,’ says Brants, ’is a legitimate constituent element of value; it is according to the cost that the producer can properly fix the value of his product and of his work.’[5]

[Footnote 1:  Brants, op. cit., p. 69.]

[Footnote 2:  De Cont., quoted by Roscher, Geschichte, p. 20.]

[Footnote 3:  Tit.  ‘Political Economy.’]

[Footnote 4:  Palgrave, Dictionary, tit.  ‘Justum Pretium.’]

[Footnote 5:  Brants, op. cit., p. 202.]

The cost of the labour of production was, however, by no means the only factor which was admitted to enter into the determination of value.  The passage from Gerson dealing with the circumstances to which the prince must have regard in fixing a price, which we quoted above, shows quite clearly that many other factors were recognised as no less important.  This appears with special clearness in the treatise of Langenstein, whose authority on this subject was always ranked very high.  Bernardine of Siena is careful to point out that the expense of production is only one of the factors which influence the value of an object.[1] Biel explains that, when no price has been fixed by law, the just price may be arrived at by a reference to the cost of the labour of production, and to the state of the market, and the other circumstances which we have seen above the prince was bound to have regard to in fixing a price.  He also allows the price to be raised on account of any anxiety which the production of the goods occasioned him, or any danger he incurred.[2]