> Weath is never created from nothing.

You can make this statement being true by moving your definition of "nothing" from economics to lay-people common sense, but then we'd be outside of a territory where we can obtain any actually reasonable observations.

> Nature is zero sum

What is "nature"? Observable universe from now to heat death of the universe? Yes. Earth in near hundred years? No.

> Robbery is also an economic transaction, and it can be positive sum if for example you don't notice.

What? How does the outcome of a transaction change depending on whether it's observed or not? Does it involve quantum particles of trees falling in the middle of desolate forests?

> That does not mean it's a good thing.

My comment didn't state anything about good or bad: these are very stupid terms and using them can't bring anything but loud voices and hurt feelings into a conversation.

I edited my comment for clarity. The point is measuring economic activity is subjective. And people have huge incentives to lie.