The most unforgettable smile I have ever come across was in a leper colony in Manchuria many years ago. I was led to an old man who spent his days sitting on a bed because his limbs had been amputated. He had lost most of his eyesight and was reading a small book with the help of a magnifying lens. The nose was gone too. The moment I touched his shoulder, he turned towards me, his face lit up and a ray of infectious, uncontaminated joy flashed across it. The positivity he radiated was coming from a deep place within him. No wonder everyone was so fond of him.