Another response to a capitalist advocate calling himself an anarchist

I don't understand the association of anarchy with anti-capitalism. With no state, there would only be capitalism. Capitalism is simply trade of goods and services amongst voluntary parties.

You seem to be under the impression that markets and Capitalism are the same thing.

Let's start with your definition of Capitalism, which you claim is "simply trade of goods and services amongst voluntary parties.".

First, trading of goods occurs in all markets (which have existed for thousands of years). This is not unique to Capitalism.

Does Capitalism involve markets? Yes! So why then do we also use the word "Capitalism"? Wouldn't that be redundant?

Capitalism is a term first used by Proudhon to refer to a unique system of exploitation that arose during the industrial revolution, and that has subsequently become the dominant mode of production.

What makes Capitalism unique are two things:

1. The use of land and human labor as commodities, and the subsequent trade of them on markets.
2. Its recognition of private property (as distinct from personal property) entitling the owner of productive capital to the proceeds of the labor of others paid to operate it.

Second, while markets can be voluntary, the unique combination of private property with commodified labor (which is the heart of Capitalism), gives rise to a system of social relations in which a minority class owns most productive property, leaving the great majority no choice but to sell their own labor for access to that property in order to earn enough money to survive. Moreover, the existence of a surplus "workforce" of unskilled labor gives complete control to the employer to set the rate of compensation. The employer uses the profit he extracted from the workers (by paying them less than the value of the goods and services they produced) to accumulate even more productive property and continue the cycle.

Thus, because the alternative would be starvation, workers are not making a voluntary decision when they sell their labor.

Third, in order to create the concept of private property, pervasive and violent force is necessary to deny access to those who lack a title to it. How else could a majority of the world's population continue to exist with wage-slavery as their only option for survival?

So amusingly enough, what differentiates Capitalism from any other economic system involving markets is precisely the fact that it imposes involuntary decisions upon people, and in so doing requires, for all practical definitions, the existence of a coercive state.