Wow. To equate capitalism with a class based, slavery driven era like that of Roman Empire is silly at best. And if you think capitalism will fail, well, all the best for you to see the status quo change. The true capitalism will take care of itself. People rise and fall in the economical ladder all the time, but capitalism is and will always be here to stay. Yes, it is based on greed, and yes, it is in our nature and there's nothing wrong with that.

I only know if you even whisper socialism anywhere, money escapes, people suffer as the result, they start to complain and since socialists know better, they silence those who complain. And Cuba started as a socialist state, you didn't establish otherwise and now it's broken, so it has to embrace capitalism inch by inch.