John Nash, described variously as mathematical genius, shadowy figure, phantom, elusive, furtive, mysterious, schizophrenic, and beautiful mind, died in a horrific cab crash on May 23, exactly a month ago, along with his wife, Alicia. He was 86 years old and was returning home from the airport after having been awarded the Abel Prize for mathematics. Several years earlier, in 1994, he received the Nobel Prize for Economics.

I met John, Alicia and their son in February of 2007, when they visited India on the invitation of the Public Diplomacy Division of the external affairs ministry. This was a personal initiative of Mr Pranab Mukhejee, the then Minister, who believed that a Nobel Laureates Lecture Series would provide a platform to the ministry to engage with the general public. John was the first Nobel Laureate to be invited. The following year, Nadine Gordimer visited India. The programme was discontinued thereafter on budgetary grounds.

Not having been a student of economics, much of my time with John and Alicia was spent in talking about other things. They openly spoke of the medication that John and his son needed to take, including the difficult period when John was diagnosed as being paranoid and delusional. With a wry smile, John remarked, \"I had moments of extreme lucidity during that time but I realised that it was a clarity others could not relate to.\"

His son, a mathematical genius, perhaps not yet in the calibre of his celebrated father, was also on medication for the same illness. He spent his time playing chess with himself and solving Sudoku.

One day, John and I returned to the hotel after a meeting. John wanted to change into more comfortable clothes and as he went to his bedroom, he glanced sideways at the Sudoku puzzle his son was working on. It could not have been a glance for more than 15-20 seconds. He returned from the bedroom wearing casuals, picked up the book, solved the puzzle and returned the book to his son. He did all this in less than a minute. It was my first meeting with John Nash and I realised I was in the presence of a genius, not because the Nobel Prize committee said so but because of what I had just witnessed.

Knowing Dr Manmohan Singh\'s passion for economics, I requested the Prime Minister\'s Office for a meeting. A reply came back quickly and I was informed that the Prime Minister would be pleased to receive Professor John Nash and his wife and their son for 10 minutes, in view of the Prime Minister\'s busy schedule. The meeting lasted for around 90 minutes and it was fascinating to see the warmth with which Dr Singh and John interacted.

The meeting began formally. We were all seated and then the Prime Minister walked in. After a while, Dr Singh, clearly impatient at the stifling formal atmosphere, got up from his chair and sat beside John. He asked his note keeper for paper and a pen. Soon John was scribbling away with the Prime Minister looking on. This was such a fascinating sight.

When tea and snacks arrived and both John and Alicia were looking somewhat diffident, Dr Singh explained each item to them personally, as he offered a plate to Alicia. He was not being the gracious host - he had simply invited friends home and was enjoying their company. Ninety minutes later, the Prime Minister personally escorted us all out and waited till the car doors were shut and we drove away. John and Alicia remarked that India was lucky to have such a wonderful and erudite person as the Prime Minister.

In Delhi, John delivered the Nobel Laureate lecture to a packed audience. He treated the talk much as he would have if he were speaking to students at Princeton or Yale. He insisted that the talk be displayed on the screen \"as the audience might have a problem with my accent\". It turned out to be an advanced economics lecture.

After the talk, many crowded around him, shaking his hand. Most had not understood a word of what he had said. When we sat down quietly to have a drink, Alicia said with a smile, \"The audience was expecting Russell Crowe.\" John responded, as wry as ever, \"And he\'s not half as good looking as I am.\"

A few days later it was time for them to leave. I bought a copy of Sylvia Nasar\'s book on which the film \'A Beautiful Mind\' was based and requested John and Alicia if they would agree to autograph it for me. Even as we were getting ready to leave for the airport, I had not received the book back with their autographs. Once their bags were loaded onto the car, they invited me for tea at the lounge and said they were happy to provide an autograph but that it was a book they did not like. I have their autographs but it is on one of the photographs in the book. It shows a young John and Alicia.

Farewell Alicia. Farewell John. May you both rest in peace.

(Amit Dasgupta, a former diplomat, heads the recently launched Mumbai campus of the SP Jain School of Global Management. The views expressed are personal. He may be reached at amit.dasgupta@spjain.org)

When John and Alicia Nash visited Delhi (Reminiscence)