12 of the most inspiring Stephen Hawking quotes to live your life by

Professor Stephen Hawking made immense contributions to the world of science.

But he also had some great things to say about life, family and disability.

Here are a collection of his best and most inspiring quotes that will live with us long after his death.

1. On human contact with aliens.

On the possibility of contact between humans and aliens: ‘I think it would be a disaster. The extraterrestrials would probably be far in advance of us. The history of advanced races meeting more primitive people on this planet is not very happy, and they were the same species. I think we should keep our heads low’.

-In Naked Science: Alien Contact, The National Geographic Channel, 2004.

and

If aliens visit us, the outcome would be much as when Columbus landed in America, which didn't turn out well for the Native Americans. We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet.

-From Into the Universe with Stephen Hawking, 2010

Frederick M. Brown/Getty Images

2. On the topic of his disability.

When I turned 21, my expectations were reduced to zero. You probably know this already because there’s been a movie about it. It was important that I came 
to appreciate what I did have.

Although I was unfortunate to get motor neurone disease, I’ve been very fortunate in almost everything else. I’ve been lucky to work in theoretical physics at
 a fascinating time, and its one of the few areas in which my disability is not a serious handicap.

It’s also important not to become angry, no matter how difficult life is, because you can lose all hope if you can’t laugh at yourself and at life in general.

-Radio Times, 2016

3. On that 'Eureka!' moment of discovering something new.

I wouldn't compare it to sex, but it lasts longer.

-Quote from a lecture at Arizona State University, April 2011

4. On how the universe will end.

All the evidence seems to indicate, that the universe has not existed forever, but that it had a beginning, about 15 billion years ago.

This is probably the most remarkable discovery of modern cosmology. Yet it is now taken for granted.

We are not yet certain whether the universe will have an end. When I gave a lecture in Japan, I was asked not to mention the possible re-collapse of the universe, because it might affect the stock market. However, I can re-assure anyone who is nervous about their investments that it is a bit early to sell: even if the universe does come to an end, it won’t be for at least 20 billion years.

-The Beginning of Time lecture, 1996

Jemal Countess/Getty Images

5. On Artificial Intelligence.

The development of full artificial intelligence could spell the end of the human race.

We cannot quite know what will happen if a machine exceeds our own intelligence, so we can’t know if we’ll be infinitely helped by it, or ignored by it and sidelined, or conceivably destroyed by it.

BBC, 2014

6. On happiness.

I have no idea [what is the meaning of life] but I remember when I was happiest. It was 1967 and the birth of my first child, Robert.

My three children have brought me great joy. 

-Interview with Piers Morgan in 2017

7. On fate and free will.

I have noticed that even people who claim everything is predetermined and that we can do nothing to change it, look before they cross the road.

-From Black Holes and Baby Universes and Other Essays

Tim P. Whitby/Getty Images

8. On humour.

Life would be tragic if it wasn't funny.

-The Science of Second-Guessing, NY Times 2004

9. On the importance of being curious.

Be curious, and try to make sense of what you see.

We live in a universe governed by rational laws that we can discover and understand.

Despite recent triumphs, there are many new and deep mysteries that remain for you to solve.

-Radio Times, 2016

10. On making mistakes.

Next time someone complains that you have made a mistake, tell him that may be a good thing.

Because without imperfection, neither you nor I would exist.

-From Into the Universe with Stephen Hawking, 2010

Getty Images for Breakthrough Prize Foundation

11. On life advice he gave his children.

One, remember to look up at the stars and not down at your feet.

Two, never give up work. Work gives you meaning and purpose and life is empty without it.

Three, if you are lucky enough to find love, remember it is there and don't throw it away.

-To Diane Sawyer/ABC News, June 2010

12. On knowledge.

Ever since the dawn of civilisation, people have not been content to see events as unconnected and inexplicable. They have craved an understanding of the underlying order in the world.

Today we still yearn to know why we are here and where we came from.

Humanity’s deepest desire for knowledge is justification enough for our continuing quest. And our goal is nothing less than a complete description of the universe we live in.

-A Brief History of Time, 1988

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