To Sen, Cambridge was like a battlefield. There were major debates between supporters of Keynesian economics on the one hand, and the "neo-classical" economists skeptical of Keynes, on the other. Sen was lucky to have close relations with economists on both sides of the divide. Meanwhile, thanks to its good "practice" of democratic and tolerant social choice, Sen's own college, Trinity College, was somewhat removed from the discord. However, because of a lack of enthusiasm for social choice theory in both Trinity and Cambridge, Sen had to choose a different subject for his Ph.D. thesis, which was on "The Choice of Techniques" in 1959, though the work had been completed much earlier (except for some valuable advice from his adjunct supervisor in India, Professor A. K. Dasgupta, given to Sen while teaching and revising his work at Jadavpur) under the supervision of the "brilliant but vigorously intolerant" post-Keynesian, Joan Robinson.[6] Quentin Skinner notes that Sen was a member of the secret society Cambridge Apostles during his time at Cambridge.[7]