"Well, they're native to other worlds, aren't they? Human beings are native to...every where."
"A single species, native to every inhabited world in the Galaxy?"
"Well..."Valeria remained confused. "I've heard of the possibility of humans originating on one world. Only one. But...that's...I mean, everyone knows that'd be...well, not likely."
"However unlikely, that is what happened. And that is the world where they originated."
Valeria stared at it, and shook her head.
"I see that you wear a watch that protects you from any harsh environment, and provides you with oxygen to breathe."
"Well, yes."
"They were I believe, invented during the settlement of the Galaxy."
Valeria looked at her watched.
"Well, you see, um, Isis does have a bit of a harsh climate, you know. Especially in the mountains, in the summers. Ra's light is unbearably hot, and, it's just the way it is. On some worlds, it's very cold, on others, warm, and, and so forth, you know. Every world is different. Isis just happens to be warmer. It's mostly a dry planet."
Daneel nodded.
"Although, well, there are some who say that once, only Cascade Valley was habitable. And human beings only lived in Cascade Valley. After a while, they spread towards the mountains, other valleys, and so forth."
"Yet part of the mountains tend to be unhabitable during certain parts of the year."
"Well, yes. They're quite beautiful, though. But of course, that's just...well, its' not possible for everyone to live in one valley. That's just things that people make up. And perhaps on Cascade Valley, because of the constellation in the western horizon. It's rather unimpressive, but it was very important to out ancestors. It told that summer was on its way, and the star at the bottom, they tended to find it rather...as a sign of a good harvest for the following year, if you know what I mean."
"You don't speak of Earth?"
"I just can't believe you."
"You perhaps speak of someone known as the Guardian. And almost all planets that were settled after Earth was radioactive were first settled by the Keepers of the Light."
"I know about the Guardian. And the Keeper of the Light, well, some say something good, and to some, very bad."
"Perhaps you should meet someone first."said Daneel, and he led her back inside.