Last month, I had the honor of greeting my colleague, Stephen Hawking, famed cosmologist, in New York, where he was being honored by the World Science Festival for all his scientific contributions. On one hand, it was a thrilling moment, seeing him surrounded by the press and then seeing him address a spell-bound audience. 

He does an extraordinary amount of traveling, speaking to audiences around the world, and seemed to be unfazed by the physical burden of moving around. Even a person who is physically fit might be exhausted by his schedule.

But on the other hand, I could see obvious signs that his illness has progressed. Years ago, when his symptoms became progressively worse, he would mumble his words, and graduate students would tediously try to translate them. Later, when he lost his voice, he used his finger to control an electronic synthesizer to communicate with the rest of the world. Now, he has lost control of even his fingers. Now, he uses blinking and facial movements to communicate, which requires an extraordinary feat of patience. It was sad seeing this great physicist being pushed around by his nurse, who also had to constantly hold his head so that it did not slump.

It is truly a testament to the human spirit to see someone like him constantly moving forward, in spite of an illness which would have defeated most mortals!