This is a scan of an aerogramme* which I received from Economics (Game Theory) Nobel Laureate John Harsanyi, after I had sent him my working paper on the formal-logic relationship between cooperative and non-cooperative bargaining theories. I studied for My PhD in Finance (option pricing) at UC Berkeley Haas School of Business, where the late John Harsanyi was an active renown professor  then. Since option pricing has rather little to do with game theory, I have never had a chance to meet John Harsanyi at Berkeley. I had the privilege of meeting him for the first time in Jerusalem, a few years after I received this aerogramme from him.

Among other places, I was invited to present this paper at the economic theroy den of lions; the joint Harvard-MIT economic theory seminar.

To see an extended abstract of that paper click on its title below:
The Strategic Sequential Bargaining Model is Generically Incompatible with the Cooperative Bargaining Theories

*For those who have never seen an aerogramme, it is an air-mail letter in the form of a lightweight sheet of stationery that folds into its own envelope for mailing.