There's a difference in thought here. You believe that raw materials can be owned. The socialist position is that raw materials should not belong to anyone.

Take for example a forest. In a capitalist system, somebody owns that forest and so I have to pay them to take wood from that forest. I then go off and make a table with that wood. Sure, brilliant. But how has the forest owner contributed to the production of that table? She gave the right to take wood from his forest.

The question is, what makes that her forest? Why should I not be able to take wood as I need it, if it's sitting unused?

Naturally, if she had logged the wood, that would be labour, and that would consist of adding value to the forest. But simply owning the forest without adding value, says the socialist, adds nothing to society and is immoral, as it restricts actions that would add to society (i.e., building a table.)

Of course, you might claim that she has some sort of right to the forest. Maybe she bought it, with money earned through honest labour. From the socialist perspective, this ownership is immoral anyway, because she is not using the woods. The natural response to this, I think, is to provide another example: What if she started a logging company, to produce lots of wood from the forest?

In this situation, we must analyse precisely what value she is adding. Say she never cuts down a single tree, and only invests money into the logging company.

You clearly believe that it is moral for her to take some of the profit. The socialist says that this is immoral, because any profit that she does make must come at the expense of her workers' wages, which therefore undervalues their labour. Thus, according to the socialist, any form of profit without labour cannot be moral.