[eli_gottlieb]

>But if mainstream economic theory is anything close to being correct, denying Marx was correct is like denying gravity. It’s just so clear based on the literature that the rate of return on investment exceeds the growth of the real economy.

Putting aside that I quite like Marx and Marxism as objects of study, Pikkety's "r > g" is simply not any of Marx's empirical theses in Capital. You are perhaps thinking of the "tendency of the rate of profit to fall", which many people considered to hold empirically in the 19th century but which came into greater dispute through the 20th century: https://en.wikipedia.org/wiki/Tendency_of_the_rate_of_profit...