Stephen Hawking became disabled because of a rare form of motor neurone disease called amyotrophic lateral sclerosis (ALS), which he developed in his early 20s and which gradually paralysed him over many years.

Quick Scoop: What Happened

  • In 1963, when he was about 21 and studying at university, Hawking was diagnosed with an early‑onset, slow‑progressing type of motor neurone disease (ALS).
  • Before his diagnosis, he began noticing increasing clumsiness , falls, and slurred speech, which led doctors to run neurological tests.
  • Doctors initially gave him only a few years to live, but his particular form of ALS progressed unusually slowly, allowing him to live into his 70s.

Over time, the disease:

  • Weakened his muscles so much that he eventually used a wheelchair full‑time.
  • Took away his ability to write and then to speak; after a tracheotomy in 1985, he relied on a computer‑based speech device he controlled with tiny movements, eventually just a cheek muscle.

Was it an accident or injury?

  • His disability did not come from an accident, trauma, or a single event.
  • It was caused by a progressive neurological disease that damaged the nerve cells controlling his muscles.

Cause of the disease itself

  • ALS is usually considered a complex condition with multiple possible contributing factors; in Hawking’s case, doctors described it as an “atypical” form, and no single clear cause was identified.

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