I’ve only just started K21, so I won't comment on anything substantive, but the mini-autobiography he presents in the introduction got me thinking. Here’s a guy who was a natural for cranking out theoretical models in economics. His career was jet-propelled, and at an age when most econ grad students are sweating out their prelims he was already on the tenure track at MIT. He could spend the rest of his life among the elite of the elite, playing cleverly with algebraic puzzles for a living. Instead, he quit, returned to France, and spent the next decade digging through archives, laboriously piecing together datasets on income and wealth distribution.
Question: how likely is this to happen? How many talented modelers, on a fast track to the highest reaches of the profession, would give it up and walk away? OK, empirically, how many have actually done this? It is essentially an accident that K21 was written in the first place.