"...my father replies that we are made to live here. We need air to breathe, water to drink, we suffocate without air and water: so why go (into space)?"
"For the same reason that makes us bring children into the world.
Because we're afraid of death and darkness, and because we want to see our image reflected and perpetuated to immortality.
We don't want to die, but death is there, and because it's there we give birth to children who'll give birth to other children and so on to infinity.
And this way we are handed down to eternity.
Don't let us forget this: that the Earth can die, explode, the Sun can go out, will go out.
And if the Sun dies, if the Earth dies, if our race dies, then so will everything die that we have done up to that moment.
Homer will die, Michelangelo will die, Galileo, Leonardo, Shakespeare, Einstein will die, all those will die who now are not dead because we are alive, we are thinking of them, we are carrying them within us.
And then every single thing, every memory, will hurtle down into the void with us.
So let us save them, let us save ourselves. Let us prepare ourselves to escape, to continue life and rebuild our cities on other planets: we shall not long be of this Earth!
And if we really fear the darkness, if we really fight against it, then, for the good of all, let us take our rockets, let us get well used to the great cold and heat, the no water, the no oxygen, let us become Martians on Mars, Venusians on Venus, and when Mars and Venus die, let us go to the other solar systems, to Alpha Centauri, to wherever we manage to go, and let us forget the Earth.
Let us forget our solar system and our body, the form it used to have, let us become no matter what, lichens, insects, balls of fire, no matter what, all that matters is that somehow life should continue, and the knowledge of what we were and what we did and learned: the knowledge of Homer and Michelangelo, of Galileo, Leonardo, Shakespeare, of Einstein!
And the gift of life will continue."