I’ve spent a week in India. The Mathematics Department of the Gujarat University in Ahmedabad has invited me to inaugurate its new premises. I like to be remembered as a mathematician, since I’m rather known as a writer, and so I willingly accepted. I spoke of mathematics and mathematicians in India. In the XII century there was a great mathematician, Bhaskacharya, who wrote a beautiful treatise with a beautiful name: Lilavati. “The playful one”. That was his daughter’s name, and thereby hangs a tale. Nothing less than the very wedding of Lilavati. It was to be celebrated with all solemnity as befitted the daughter of such a father, and, concretely, the moment in which the bride’s and bridegroom’s hands were joined by the priest for the first time, had to be calculated with mathematical exactness. Here the father’s knowledge excogitated a new and original way. Better than sundials or hourglasses, to calculate the exact moment as it fitted his knowledge and his science. He took a large lotus leaf, round, flat, with lifted border, and bored delicately a tiny whole in it such that the water would come in through it little by little, and the moment the leaf sank would be the moment of the joining of the hands. Poetical and scientifical. Everything was done accordingly, the leaf was getting heavier with water, and all expected the exact moment. But the moment was not arriving. Something had gone wrong. The water had stopped getting into the leaf. They worried and examined the leaf closely. There they found to their dismay that one of the pearls of the bride’s necklace had got lose and had blocked the hole. The water was still, the stellar moment had passed, and the wedding could not take place. Wedding takes place only once, and as its only opportunity had been irretrievably lost, Lilavati could not marry for life. This was a disgrace for her and for the whole family, but what could they do to console her?

Here is where the father stepped forward and told her: “I’m sorry with all my soul that this has happened, my child, and that you now cannot be married in your whole life. But it order to make it up for you in this great suffering, and in order to make you name immortal in all generations to come, I’m going to write a mathematical treatise which will be the best and most advanced of all times; and I’m going to put your name to it. It’ll be know as the “Lilavati”, so that all will pronounce your name through the ages. He wrote it, and it survives to this day. It contains theorems and problems, and, apart from mathematics, it interests us for the idea it gives of social life in the XII century in India. Mathematical problems in our textbooks deal with weights and measures, forces and distances, trains and planes, angles in football and orbits of satellites, while those in the Lilavati speak of spears and arrows, snakes and peacocks, Brahmins and ceremonies. A mirror to society. Just one sample which is not found in our textbooks:

“A prostitute is making love to a client. Her necklace breaks in such a way that one fifth of the pearls falls on the bed, one third fall to the ground, one sixth remain on her body, and one tenth in her lover’s hands. If there are 6 pearls still left on the necklace, say, oh devout worshipper of Vishnu, how many pearls were there on the whole?

Whether Lilavati was consoled or not we don’t know, but the example does give us another conclusion, that is the naturalness and matter-of-factness with which sex was mentioned in the XII century, which is a good lesson for our own society and its deep complexes in the matter. By the way, the necklace had 30 pearls. It is enough to write down the equation, clear the fractions and solve for the unknown. After such digressions I spoke to them of my own studies at the Madras University (Chennai).The so called “Modern Algebra” (set, groups, rings, fields, matrices, vector spaces) had just come into being in France in the Bourbaki school (a character that never existed but whose name, with a touch of humour, proposed the new discoveries. They even publishes his biography! There was in those days in Madras a Jesuit priest, father Racine, who introduced Modern Algebra in India and taught it to us as the special subject in our last year. That means that when I reached Ahmedabad, I was the only person to know the new subject. I was, accordingly, asked to give that summer a course to postgraduate teachers, and so I began teaching the teachers before I could teach the students. I was lucky that way. I later attended international mathematical congresses, beginning with the one in Moscow in 1964 in which I heard Michel Artin declare that “modern mathematics have become so complex that all important theorems are false, and all true theorems are useless.” This was no so unexpected, however, if we remember the definition Bertrand Russell had previously given: “Mathematics is the science in which we do not know what we are talking about, and we don’t care whether what we say is true.” I did plunge into mathematics wholeheartedly and I enjoyed my classes, and even correcting examination papers, which are always amusing given the bloomers committed by the students.

All this and much more I recollected with nostalgic joy before all those professors who have lived with me all those eventful years. A whole generation of mathematicians. I also remembered with them what some literary critics wrote about my style in my articles and books in the Gujarati language. One of them said: “One can see that Father Valles is a mathematician in the clarity and logic of his literary style.” Another wrote: “The only thing that one cannot explain is that Father Valles may be a mathematician, given the simple and transparent style of his writings.” Please yourself.

As you see, I’ve have a happy time in India. I always say this is my last visit, but I’ve already got an invitation for next year.