Dan Drezner reports on a small tiff= between Paul Samuelson and Jagdish Bhagwati over outsourcing. It contains a good line that tells you a lot about neoclassical economics:

But Mr. Bhagwati … says he doubts whether the Samuelson model applies broadly to the economy. “Paul and I disagree only on the realistic aspects of this,” he said.

In contrast, Marxists tend to agree fully on the realistic aspects of things but disagree about the unrealistic ones, such as when exactly the revolution is coming, who will be in charge, and whether people or robots will clean the toilets afterwards.