Explanation:
Professor Hawking had just turned 21 when he was diagnosed with a very rare slow-progressing form of ALS, a form of motor neurone disease (MND).
He was at the end of his time at Oxford when he started to notice early signs of his disease. He was getting more clumsy and fell over several times without knowing why.
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In comments published in a 2002 British Medical Journal article close to his 60th birthday, Professor Hawking recalled going to hospital for medical tests.
"I was in for two weeks, during which I had a wide variety of tests. 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.
"I gathered, however, that they expected it to continue
