Physicist, cosmologist and obsessor of black holes Stephen Hawking turns 70 Sunday, despite a diagnosis of Lou Gehrig’s disease that doctors said would kill him almost five decades ago. Many scientists are taking the birthday as a chance to reflect on what the man taught us in his brilliant career.

Stephen Hawking. (MARKUS SCHREIBER/AP)

Below, six other lessons Hawking has taught us in his 70 years:

1. We will never have all the answers.

At the end of a lecture in the Royal Albert Hall in Kensington, England, in 2010, Hawking was asked: “Do you think it will come the time that people will learn everything about physics?” The scientist quickly responded: “I hope not!” And when a reader of Time magazine that same year asked him whether it felt like a huge responsibility to have all the answers, Hawking wrote back: “While physics and mathematics may tell us how the universe began, they are not much use in predicting human behavior because there are far too many equations to solve. I'm no better than anyone else at understanding what makes people tick.”

2. Knowledge is best put to use when shared.

Despite its difficult subject matter, Hawking’s “A Brief History of Time” has been read by legions of people because the physicist made it so accessible. A popular story goes that Hawking’s publisher told him readership would be cut in half for every equation in the book, so Hawking included only one: E = mc².

“The fact is that information in his mind would be useless to anyone else if he wasn’t able, somehow, to communicate it effectively,” Science blogger Mic Farris writes.

3. Learn the lessons of history.

Hawking fielded questions from the BBC this week on what might happen if humans discover other intelligent life. Hawking’s response: Know your history. “The discovery of intelligent life elsewhere in the universe would be the biggest scientific discovery ever,” he said. “But it would be very risky to attempt to communicate with an alien civilization. If aliens decided to visit us then the outcome might be similar to when Europeans arrived in the Americas. That did not turn out well for the Native Americans.”

5. Study what fuels your passion.

When the Washington Post interviewed Errol Morris, director of the film adaptation of “A Brief History of Time,” in 1992, Morris explained why he believed Hawking was so fascinated with the study of black holes: “To me, it's like some real-life Edgar Allan Poe story, a version of the premature burial — being essentially buried alive inside of one's self. . . . When he was 21 years old, he was given a death sentence with 2 1 / 2 years to live, and in the nearly 30 years since then, he has become increasingly incapacitated. And what is the central objective of his inquiries? Black holes. Stars that collapse in on themselves, implode, become so incredibly dense that nothing can escape their gravitation field . . . To me, there’s a very close metaphorical connection.”

5. Never lose your voice.

Because of his motor neuron disease, Hawking had to undergo a tracheotomy in 1985 that removed his ability to speak on his own. But he never stopped talking. Like movie critic Roger Ebert or the protagonist of “The Diving Bell and the Butterfly,” Hawking adopted his own way of speaking — by using a computer that picks up the twitching movements of his right cheek.

6. Genius shouldn’t always be associated with precocity.

Hawking admitted in the same Royal Albert Hall lecture that he did not learn to read until he was 8 years old. He also said he was a lazy student at Oxford University, his classwork untidy and his handwriting the “despair of my teachers.” Late bloomers, take heart.