>Some marxists tell me capital and natural capital are, sometimes they're just factories and resources and shit.
>So how do you give that to the working class? What does that mean?
How do shareholders own a company?
>That every person on earth owns the land?
They own it collectively, yes
>Why couldn't someone just knock down your house and build one of their own?
Because it's not their personal property, and one individual doesn't get to deprive another person of his non-capital personal property. If collectively society agrees your illegal settlement on the bank should be demolished, and the other guy should be able to build a house there, then yes, it could happen. The part you don't seem to get is that it is a democratic decision of society, not one individual versus another individual.
>Or if I'm a member of the working class, why can't I decide to do with the resources myself?
You can, if it's not capital
>If I build a factory does everyone else just take it away?
You get fairly compensated by society for your labor, according to what society feels is fair, just as if you had been hired by someone to build a factory. You don't own the factory, society does, and society as a whole gets democratically to decide what to do with it.
If you're able to convince society, they may let you run the factory, but you have no explicit rights due to private ownership, and your position as manager of the factory is at the will of the people.
>Seems like way too big of an oversight. What the fuck was Marx thinking?
The part where rabid individualists don't understand what society or democratic decision making is.
Basically, you should just imagine that every company is a public company, and every adult individual is an equal part shareholder. There's no individual that owns 51% of the shares, and the CEOs and executives and the board are at the mercy of society as a whole, because society as a whole are the shareholders.