After 3 trips to space, he's realized something no one says.
People who've seen Earth from space often have a pretty cosmic attitude about the place.
Astronaut Chris Hadfield wants everything and everyone to stop for a minute. Hadfield says we're all going too fast to realize something really important.
But there are lots of reasons to be hopeful.
And it's not just because of our amazing technology. Though, of course...
There's something basic about the human spirit.
There are so many great signs of progress and things to be thankful for, like incredible advances in survival rates for our youngest people.
And then there's all this.
Things are getting better.
And not that slowly either.
So Hadfield says he's optimistic.
Hadfield believes everyone else should be optimistic, too, because it's our best way forward together.
"Remember, nobody changes the world on their own." — Chris Hadfield
Here's the video he made explaining his case.