India, July 21 -- My father was the eldest of four surviving siblings - three brothers and a sister. In truth, he was the fifth child born to my grandparents, but the first to survive. The four before him died either during childbirth or shortly thereafter. He was born in 1917, the year of the Russian Revolution, when India was still a British colony. In 1990, the average life expectancy in India was a shocking 22 years.

Thanks to advances in medical science, the average life expectancy in India has crossed 70, and in my home state of Kerala, it is well over 75. Diseases that once wiped out entire communities are now preventable, treatable, and often curable. Today, it is no longer unusual to meet people in their 90s or even centenarians...