Variable Capital
Corresponding to “constant capital”. In the process of capitalist production, the part of capital that exists in the form of labor-power is called variable capital (denoted by the letter V). The value of variable capital is the only source of surplus-value. In the production process, while exploiting concrete forms of labor and transferring the value of the means of production into the new product, the worker has created a new value that is greater than the value of labor-power. This new value includes not only the value of labor-power, but also a surplus-value, so that a valorization of value [expansion of value] takes place in the original value. Therefore, this part of capital is called “variable capital”.