Without an end to the burning of fossil fuels, coal especially, most of us will live shorter lives. I'm hopeful, but very, very concerned.

Everyone you will ever meet knows something you don't.

We are just a speck, on a speck, orbiting a speck, in the corner of a speck, in the middle of nowhere.

To leave the world better than you found it, sometimes you have to pick up other people's trash.

Science is the best idea humans have ever had. The more people who embrace that idea, the better.

You and I are made of stardust. We are the stuff of exploded stars. We are therefore, at least 1 way that the Universe knows itself. That, to me, is astonishing.

There's nothing I believe in more strongly than getting young people interested in science and engineering, for a better tomorrow, for all humankind.

I speak with dogs frequently. They don't really talk, but I feel they're communicating.

The natural world is a package deal; you don't get to select which facts you like and which you don't.

The more you find out about the world, the more opportunities there are to laugh at it.

Science is the best thing humans beings have ever come up with. And if it isn't, science will fix it.

All times are sacred

Fear knows no borders, and the terminology of hate has seeped into every aspect of life.

I owe everything to a system that made me learn by heart till I wept. As a result I have thousands of lines of poetry by heart. I owe everything to this.

There is nothing better fitted to delight the reader than change of circumstances and varieties of fortune.

Since the world began has any man ever been able to know what would happen tomorrow? The world of men is today. I'm asking you to open your heart today. Tomorrow belongs to Allah.

I've been through a lot in life, and had some ups and downs. It's what's led me to this day.

We don't fall in love and then get married; instead we get married and then learn what love requires.

When you want to win a game, you have to teach. When you lose a game, you have to learn.

If I could reach up and hold a star for every time you made me smile, the entire evening sky would be in the palm of my hand.

I am a citizen of the world, and I have met, in my time, with so many different sorts of virtue, that I am puzzled, in my old age, to say which is the right sort and which is the wrong.