On the other hand, that part of capital represented by labour-power does, in the process of production, undergo an alteration of value. This part of capital is continually being transformed from a constant into a variable magnitude. I therefore call the variable part of capital, or shortly, variable capital. However, this conclusion seems not to hold in perfect competition. No real inflation, i.e. the inflation rate equals to the interest rate, and vice versa.
Perfect information is available efficiently.
In such a perfect competitive market, the economic profit of the capitalist will be zero. The conclusion is actually a common sense in today's economics. It is so well known that every economics undergraduates understand it, and that I do not think it necessary for me to cite any great economist to prove this doctrine. This doctrine implies that since the economic profit is zero, the account profit will be the interest rate, which is also the average rate of capitalist's account profits. Based on the above discussion, I will demonstrate that no exploitation exists in perfect competition.