Slightly off topic, but I don't think that the argument "capitalism is the system which worked better) is valid. It's not that it's wrong, per se, but I think it's an implication of mankind evolution and not the capitalist system itself.

In more concrete terms: if you pick any given point in time, you'd probably be able to say the same without being wrong. At date X, the social system in practice is/was the one which worked better up until that X point; it's because we've been evolving somewhat continuously, not because the system per se.