It was interesting to read in the media that Gruber has not even been seen in public lately, so I went to his MIT web page to look up his class schedule.
Lo and behold, Gruber has no visible means of support.
By this i mean not that he is unaffiliated with a university, but that he does not actually teach, and is not an emeritus... at least not yet.
So what do active university professors do when they are not teaching? Either sabbaticals or full time research supported by external grants.
I sent an inquiry to MIT Economics Department Head Whitney Newey
http://economics.mit.edu/faculty/wnewey
asking what Prof. Gruber has been doing these last few years and what his sources of funding are.
I think the motivations of people are best understood when their sources of funding are clearly identified.
Jonathan Gruber
Contact Information
Phone: (617) 253-8892
Fax: (617) 253-1330
Email: gruberj@mit.edu
Address:
MIT Department of Economics
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Bldg E17-220
Cambridge MA 02139
Support Staff:
John Arditi
Phone: (617) 253-8887
Email: arditi@mit.edu