Editing Foundation and Earth (section)

==Relationship with other works==
Although hinted at in ''Foundation's Edge'', this book was the first book of the series that merged it with Asimov's [[Robot series (Asimov)|''Robot'' series]]. The radioactive-Earth theme was begun in ''[[Pebble in the Sky]]'', which is set thousands of years earlier. [[R. Daneel Olivaw]]'s role in the events of that novel would later be described in the prequels.

This book serves as a kind of epilogue to the [[Robot series (Asimov)|''Robot'' series]]. Asimov describes what has become of the Spacer worlds of Solaria and Aurora, described extensively in ''[[The Naked Sun]]'' and the ''[[Robots of Dawn]]'', respectively.  The author also reveals what has happened to Earth, as described in ''[[Robots and Empire]]''.

The book ''[[Nemesis (Asimov)|Nemesis]]'', predating the timeline and events found in the ''Foundation'' and ''Robot'' series, hints at the motives and origins of [[Gaia (Asimov)|Gaia]].  Humans had a very early contact with the sentient moon [[Erythro (Asimov)|Erythro]], a very abstract alien intelligence.

In'' [[Foundation's Triumph]]'', the last book in the Second Foundation Trilogy (authorized by Asimov's estate), another possible future for the Galaxy is discussed. In a conversation between Hari Seldon and Daneel Olivaw, Seldon discusses the possibility that the Foundation will in fact incorporate Gaia into the Second Galactic Empire. He then bets that in a thousand years, well after Galaxia should have been established and removed the need for formal education, editions of the Encyclopedia Galactica will be published. The fact that two versions of the Encyclopedia are published after this deadline seems to lend credence to the view that Seldon won the bet.