I left Delhi in 1989 and remember very little of how life used to be then. Increasingly, in my recent visits to Delhi, I've started to realize that the city has become intellectually very lively. It makes me want to discover the city over and over again.

Could your medicine be a cell, not a pill? Could your medicine be an organ that's created outside the body? Could your medicine be an environment?

In Paris, friend of Bequerel’s, a young physicist-chemist couple named Pierre and Marie Curie, began to scour the natural world for even more powerful chemical sources of X-rays. Pierre and Marie (then Maria Sklodowska, a penniless Polish immigrant living in a garret in Paris) had met at the Sorbonne and been drawn to each other because of a common interest in magnetism.

In the laboratory, we call this the six-degrees-of-separation-from-cancer rule: you can ask any biological question, no matter how seemingly distant-what makes the heart fail, or why worms age, or even how birds learn songs-and you will end up, in fewer than six genetic steps, connecting with a proto-oncogene or tumor suppressor.

One swallow is a coincidence, but two swallows make summer.

I began wondering, can one really write a biography of an illness? But I found myself thinking of cancer as this character that has lived for 4,000 years, and I wanted to know what was its birth, what is its mind, its personality, its psyche?

Pharmacology is benefited by the prepared mind. You need to know what you are looking for.