The system of social organization that emerged with capitalism needed to have elements of basic sociality, ethics, and goodwill.
It could definitely not have succeeded without these. Modernity succeeded because of goodwill, and because of the ethical behavior of the humans making up society (this is just what is lacking in what Loretta Napoleoni describes as "Rougue Economics"). It is not some kind of dry, mechanical causality like that which is expressed mathematically ---- a supply-demand graph/curve.
All societies, and modern ones are not excluded, need their deeply human, cultural, social ethical component ---- the system of capitalism of the last 200 years being no exception.
So capitalism is dependent on goodwill ---- and goodness.
Now, notice how this creates a cognitive dissonance with the predominant and mainstream approach. What they emphasize is economic rationality -- not ethical sociality.