To Sir, with Love
Pinaki Mitra, Pinaki-da to us, was my Mathematics and Statistics teacher in Patha Bhavan High School, Calcutta. He was the most influential teacher I have ever had. I have been lucky enough to have some great Economics teachers in Presidency College, and the two universities I attended, Delhi School of Economics and Harvard University. I use the word influential in the sense of having the biggest impact on future trajectory from a given starting point and direction.
Pinaki-da not only taught these subjects from a conceptual point of view, far from the standard prevailing style of teaching them, which was largely techniques for problem-solving with an eye to the examination. I had taken Mathematics and Statistics somewhat halfheartedly in High School, to keep some options open after deciding not to pursue the hard sciences and the medical-engineering route. My real love was literature at that point, but I wanted to learn a bit of economics to understand the economic and political problems around us, being a precocious politically opinionated teenager. After a few lectures by Pinakida on real numbers, limit, continuity, and probability, I was transported to a magical world. There was no looking back.
After all these years, I still can feel that intoxicating sensation after understanding some particularly subtle concept from Pinaki-da, only to realise later there were more layers of mystery to it. Near, but yet, far. Like limit and continuity. The game would continue.
By the time I graduated from High School, I was definitely "converted". Whatever I studied, Mathematics would be part of it. And, I wanted to do research. The question was whether I would pursue Mathematics or Statistics as my main subject in college, or Economics. I ended up choosing Economics.
Pinaki-da introduced us not just to Mathematics and Statistics, but also to Philosophy, Literature and Linguistics (the last being his passion around that time). I learnt about the works of Noam Chomsky, Bertrand Russell, Ludwig Wittgenstein, and John Von Neumann, among many others in the living room of his house in Picnic Gardens, Calcutta around 1985-86.
It is rare to have someone like Pinaki-da as a teacher and a mentor. Even though he was a mathematician by training (and topped the University exams from Presidency College), he was interested in everything under the sun. I still remember how he related the last scene of the famous Satyajit Ray film Charulata -- where the hands of the protagonists, the estranged couple Bhupati and Charu, approach each other but then there is a freeze shot -- to the concepts of limit and continuity in calculus.
I was lucky to have such a teacher. I plan to write more about Pinaki-da in the future.