Chartalism & MMT have become so identified with "the left" today that many would likely be surprised that Marx had this to say about money:
"the issue of paper money must be restricted to the quantity of gold (or silver) which would actually be in circulation, and which is represented symbolically by the paper money… If the paper money exceeds its proper limit, i.e. the amount in gold coins of the same denomination which could have been in circulation, then, quite apart from the danger of becoming universally discredited, it will still represent within the world of commodities only that quantity of gold which is fixed by its immanent laws."
- Capital, Vol. 1