Small

Looking down from his perch on the edge of space, Felix Baumgartner remarked:

Sometimes you have to be really high,
to see how small you really are.

It turns out that this feeling is a well documented phenomena dubbed the Overview effect. When a person gazes upon Earth from outer space, they have a profound sense of perspective, a realization of fragility, that humanity and all life as we know it is completely dependent on a single planet and its thin atmosphere.

It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn't feel like a giant. I felt very, very small.
— Neil Armstrong

So while the first astronauts to the moon went as technicians, they came back as humanitarians. In the words of William Anders, "We came all this way to explore the moon, and the most important thing is that we discovered the Earth."

The view of the Earth from the Moon fascinated me—a small disk, 240,000 miles away. It was hard to think that that little thing held so many problems, so many frustrations. Raging nationalistic interests, famines, wars, pestilence don't show from that distance.
— Frank Borman, Apollo 8

As Voyager 1 was approaching the edge of our Solar System, Carl Sagan convinced the team at NASA to rotate the probe and send one last photograph back. A photograph portraying the earth as a tiny blue dot contrasted against the emptiness of space.

This photograph wasn't taken for purely scientific reasons, but had a deeper significance which Sagan elaborated on in his book Pale Blue Dot:

There is perhaps no better a demonstration of the folly of human conceits than this distant image of our tiny world.

Look again at that dot. That's here, that's home, that's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The Earth is a very small stage in a vast cosmic arena.

It's no coincidence that the word small is endemic to experiences of space. In all these quotes from astronauts, the word comes up time and time again. Compared against the vastness of space, all our quarrels, conceits and concerns fade away into insignifiance.

It's for this reason, the Overview effect, that I am extremely excited about the prospects of Space Tourism. With more people viewing the Earth from afar, perhaps the world will gain a little more perspective, and a better sense of proportion.