[adabsurdo]

Mr. Krugman's point, very succintly, is that money is power, political and otherwise, and that as it concentrates into fewer hands (as has happened to a huge extent in the last 30 years), those at the top start to behave like a ruling class - an oligarchy.

it will always be the case that politicians are more responsive to those with money, especially with the current judicial doctrine in the USA, that money is speech and therefore all attempts to regulate its use in politics is basically unconstitutional. that's the real issue with wealth inequality.

Mr. Mankiw is just arguing sideways to Mr. Krugman by making the very obvious point that more education betters your life's odds. And since Mr. Mankiw is a very bright guy, I can't help but think that he's doing this on purpose to muddy the discussion.