If there's no one fundamental way that economies work, then there's no such thing as economies in general. So what are economists comparing when they say capitalism works better than communism? What are they talking about?

Of course, there's the ordinary meaning of "economy" in English, but presumably that folk concept doesn't suffice for a science. We'd expect that economists would have a much better understanding of what economies in general are than the folks who say economies are where business happens. I'm pretty sure it's fair to expect of a genuine science--whether it be a natural or a social one--that the scientists should mostly agree on the fundamentals of their discipline, and that the agreement should be based not on mere commonsense, prejudice, or tribal politics, but on a rigorously obtained theory of how the subject matter works. The subject of economics isn't capitalism or communism, but economies. So what, in general, are economies? According to you, economists have reached no consensus on that issue. And according to me, that means economics isn't yet a science.