Capital is Money. And Capitalism is money organized to make more money.
Money making more money, makes more money available. This creates a society with big advantages, and big disadvantages.
Lots of money is available for big projects – transportation (railroads and steamship lines) – and for manufacturing (for making factories). These combinations make nations powerful – and also make for income inequality. More power is created, but this power is not equally distributed.
Something else is necessary to make all this work – to lessen the inequality, and make bigger pieces of the pie available for everyone. And this something else has to be, to begin with – an awareness that this something else is needed.
Once we know what is needed, we can try different ways of making it happen. Always keeping in mind, what we want to do. Make a better world.