While Hawking first began to notice problems with his physical health while he was at Oxford—on occasion he would trip and fall, or slur his speech—he didn't look into the problem until 1963, during his first year at Cambridge. For the most part, Hawking had kept these symptoms to himself. But when his father took notice of the condition, he took Hawking to see a doctor. For the next two weeks, the 21-year-old college student made his home at a medical clinic, where he underwent a series of tests.
"They took a muscle sample from my arm, stuck electrodes into me, and injected some radio-opaque fluid into my spine, and watched it going up and down with X-rays, as they tilted the bed," he once said. "After all that, they didn't tell me what I had, except that it was not multiple sclerosis, and that I was an atypical case."
Eventually, however, doctors did inform the Hawkings about what was ailing their son: He was in the early stages of amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease). In a very simple sense, the nerves that controlled his muscles were shutting down. Doctors gave him two and a half years to live.
It was devastating news for Hawking and his family. A few events, however, prevented him from becoming completely despondent. The first of these came while Hawking was still in the hospital. There, he shared a room with a boy suffering from leukemia. Relative to what his roommate was going through, Hawking later reflected, his situation seemed more tolerable. Not long after he was released from the hospital, Hawking had a dream that he was going to be executed. He said this dream made him realize that there were still things to do with his life.
But the most significant change in his life was the fact that he was in love. At a New Year's party in 1963, shortly before he had been diagnosed with ALS, Hawking met a young languages undergraduate named Jane Wilde. They were married in 1965.
In a sense, Hawking's disease helped him become the noted scientist he is today. Before the diagnosis, Hawking hadn't always focused on his studies. "Before my condition was diagnosed, I had been very bored with life," he said. "There had not seemed to be anything worth doing." With the sudden realization that he might not even live long enough to earn his PhD, Hawking poured himself into his work and research.