[arcticbull]

Not all investments are positive sum - metals are zero sum, proof of work coins are negative sum.

You can’t build a building on top of nothing so if land has a building on it you can apportion some of the productivity of the building to the land itself.

Agreed land without improvements is zero sum.

[sudosysgen]

I didn't mean for society, I really meant for the investors, and investor in real estate has the option to rent it out so buyers of real estate operate a positive sum business.