Notes on Ricardo’s Principles (5) – 価値 4
生産性の向上と賃金鉄則
If the shoes and clothing of the laborer could, by improvements in machinery, be produced by one-fourth of the labor now necessary to their production, they would probably fall 75 percent; but so far is it from being true that the laborer would thereby be enabled permanently to consume four coats, or four pair of shoes, instead of one, that it is probable is wages would in no long time be adjusted by the effects competition, and the stimulus to the population, to the new value of the necessaries on which they were expended. If these improvements extended to all the objects of the laborer’s consumption, we should find him probably, at the end of a very few years, in possession of only a small, if any, addition to his enjoyments, although the exchangeable value of those commodities, compared with any other commodity, in the manufacture of which no such improvement were made, had sustained a very considerable reduction; and though they were the produce of a very considerably diminished quantity of labor.
リカードは生産性の向上により、賃金はいったんは上昇するが、それは人口増を引き起こし、結局、もとの生存可能最低水準に下落する、という趣旨のことを述べる。
「機械の改良による生産性の向上により、靴やコートがこれまでの4分の1の労働で生産で生産されるようになれば、それらの靴やコートの価値は75%下落するだろう。しかし、労働者は、同一の賃金で長期間にわたって、4つの靴、4つのコートを買うことはできない。それは、競争の作用、そして賃金の上昇(による購買力の上昇; KN注)が人口増を引き起こすからである。」(機械の改良による生産性の向上->賃金の上昇->人口増->賃金はもとの水準(=生存可能水準)への下落) つまり、リカードは、労働の限界生産力=(生存可能水準)賃金、ということをいっていることになる。但し、リカードの時代には限界価値概念は、明示的(explicit)な形では経済学に登場しておらず、リカードは暗示的(implicit)にこのことを言っているといってよい。また、リカードは均衡賃金の決定にあたり、生産要素間の限界生産力均等の法則でなく、賃金鉄則(生存可能水準に賃金は決定される)によっている、ということは指摘しておかなければならないだろう。
商品の相対価値
It cannot then be correct to say with Adam Smith, “that as labor may sometimes ‘purchase’ a greater and sometimes a smaller quantity of goods, it is their value which varies not that of the labor which purchases them;” and therefore, “that labor, ‘alone never varying in its own value’, is alone the ultimate and real standard by which the value of all commodities can at all times and places be estimated and compared;” – but it is correct to say, as Adam Smith had previously said, “that the proportion between the quantities of labor necessary for acquiring different objects seems to be the only circumstance which can afford any rule for exchanging them for one another;” or in other words that it is the comparative quantity of commodities which labor will produce that determines their present or past relative value, and not the comparative quantities of commodities which are given to the laborer in exchange for his labor.
リカードは、ここでアダム・スミスを引用し、商品の価値は、それぞれの商品の生産に必要とされる労働(量)により決定され、商品の相対価値もまた、それぞれに投入された相対的労働量により決定される、と述べる。
実証科学としての経済学
Two commodities vary in relative value, and we wish to know in which the variation has really taken place. If we compare the present value of one with shoes, stockings, hats, iron, sugar, and all other commodities, we find that it will exchange for precisely the same quantity of all these things as before. If we compare the other with the same commodities, we find it has varied with respect to them all: we may then with great probability infer that the variation has been in this commodity, and not in the commodities with which we have compared it. If on examining still more particularly into all the circumstances connected with the production of these various commodities, we find that precisely the same quantity of labor and capital are necessary to the production of the shoes, stockings, hats, iron, sugar, etc., but that the same quantity as before is not necessary to produce the single commodity whose relative value is altered, probability is changed into certainty, and we are sure that the variation is in the single commodity: we then discover also the cause of its variation.
ここで、リカードは、2つの商品の相対価値が変化した場合にどちらの価値が変化したかの検証方法を述べる。この場合、まず第1の商品を取り上げ、それを他の多くの商品のと比較する。次に第2の商品と他の多くの商品と比較する。それによってどちらの商品に変化があったかを知ることができる、という科学的なアプローチについて言及している。これは当たり前といえば当たり前の話であるが、経済学は実証的科学、サイエンスである、というリカードの姿勢を表したものといえる。現実の経済には無数の変数があり、それらを同時に扱うとわけがわからなくなってしまう。わかったようでわからない経済評論が多いのは今日も同様である。それに対する戒めといってよいだろう。
(2015.8)
