Capital:Volume 1, Chapters 19-22 by Karl Marx

Chapter 19: The Transformation of the Value (and Respectively the Price) of Labour-Power into Wages

1. "If demand and supply balance, the oscillation of prices ceases, all other circumstances remaining the same." - 678
2. "As the value of labour is only an irrational expression for the value of labour-power, it follows of course that the value of labour must always be less than its value-product, for the capitalist always makes labour-power work longer than is necessary for the reproduction of its own value." -  679
3. "the worker is paid after he has given his labour. In its function as a means of payment, money realizes, but only subsequently, the value or price of the article supplied" - 681
4. "the capitalist...the only thing that interests him is the difference between the price of labour-power and the value which its function creates." - 682

Chapter 20: Time-Wages

1. "The sale of labour-power, as will be remembered, always takes place for definite periods of time. The converted form in which the daily value, weekly value, etc. of labour-power is directly presented is hence that of time-wages" - 683
2. nominal wages: "The sume of money which the worker receives for his daily or weekly labour...his wages estimated in value." - 683
3. "The unit of measurement for time-wages, the price of the working hour, is the value of the day's labour-power divided by the number of hours in the average working day." - 685
4. "here we come upon the origin of the sufferings which arise for the worker out of his being insufficiently employed. If the hour's wage is fixed in such a way that the capitalist [is]...only to pay wages for the hours during which he chooses to employ the worker, he can employ him for a shorter time than that which is originally the basis of the calculation of the wages for the hour." - 686
5. "The capitalist can now wring from the worker a certain quantity of surplus-labour without allowing him the labour-time necessary for his own subsistence. He can annihilate all regularity of employment, and according to his own convenience, caprice, and the interest of the moment, make the most frightful over-work alternate with the relative or absolute cessation of work." - 686
6. "The competition thus created between the workers allows the capitalist to force down the price of labour, while the fall in the price of labour allows him, on the other hand, to force up the hours of work still further." - 689

Chapter 21: Piece-Wages

1. "Piece-wages are not in fact a direct expression of any relation of value. It is not, therefore, a question of measuring the value of the piece by the labour-time incorporated in it. It is rather the reverse: the labour the worker has expended must be measured by the number of pieces he has produced." - 694
2. "Since the quality and intensity of the work are here controlled by the very form of the wage, superintendence of labour becomes to a great extent superfluous." - 695

Chapter 22: National Differences in Wages

1. "In proportion as capitalist production is developed in a country, so in the same proportion, do the national intensity and productivity of labour there rise above the international level." - 702
2. "experience shows that even if the level of wages more or less corresponds with the average intensity of labour, the relative price of labour (i.e. the price of labour in relation to the product) generally varies in the inverse direction." - 705