A conception not reducible to the small change of daily experience is like a currency not exchangeable for articles of consumption; it is not a symbol, but a fraud. George Santayana
As the revenue of the farmer is realized in raw produce, or in the value of raw produce, he is interested, as well as the landlord, in its high exchangeable value, but a low price of produce may be compensated to him by a great additional quantity. David Ricardo
If a commodity were in no way useful, - in other words, if it could in no way contribute to our gratification, - it would be destitute of exchangeable value, however scarce it might be, or whatever quantity of labour might be necessary to procure it. David Ricardo
If the quantity of labour realized in commodities, regulate their exchangeable value, every increase of the quantity of labour must augment the value of that commodity on which it is exercised, as every diminution must lower it. David Ricardo
In stating the principles which regulate exchangeable value and price, we should carefully distinguish between those variations which belong to the commodity itself, and those which are occasioned by a variation in the medium in which value is estimated, or price expressed. David Ricardo
