I feel like capitalism is what happens without any intervention. It is the economy that results from individuals acting as individuals, but I suppose with a social species there's an argument to be made that collectivist economic principle is equally natural.

I'd argue that even that social instinct only plays out in full form in regards to family and friends, so that it stills ends up in a large-scale, competitive, capitalist structure.

There are, of course, many examples to the contrary though.