When he was 21, Stephen Hawking was diagnosed with motor ... book "A Brief History of Time." Here are a dozen quotes showing Hawking's approach to science and to life.

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Stephen Hawking was born on the 300th anniversary of Galileo's death. He has come to be thought of as the greatest mind in physics since Albert Einstein. With similar interests -- discovering the ...

Stephen Hawking used his fame to raise awareness of what people need to thrive when they're living with a disability. Credit: AFP/Getty Images When Stephen Hawking spoke, the world listened.