MacDonald was a political radical, and Isaac Asimov later recalled that Heinlein was, like her, " a flaming liberal.

Therefore, in a much later book, Robots and Empire ( 1985 ), Asimov provided a different origin for the future Earth's radioactivity-making it the result of a gradual process in the course of which human and other life could survive.

Trantor was first mentioned in a short story by Asimov, ' Black Friar of the Flame ', later collected as The Early Asimov, Volume 1.

In the Asimov canon, where events of this time are depicted mainly from a Foundation perspective, the Fall of Trantor is mentioned only as a piece of faraway news and in various later short references.

According to the original Foundation Trilogy ( 1951 ), Asimov states ( by way of the Encyclopedia Galactica ), "... the impossibility of proper administration ... under the uninspired leadership of the later Emperors was a considerable factor in the Fall.

Four years later, Asimov followed up with yet another sequel, Foundation and Earth ( 1986 ), which was followed by the prequels Prelude to Foundation ( 1988 ) and Forward the Foundation ( 1993 ).

However, when Asimov decided decades later to retroactively integrate the universe of his Foundation and Galactic Empire novels with that of his Robot stories, a number of changes and minor discrepancies surfaced — the character R. Daneel Olivaw was established as having existed for some 20, 000 years, with the original Robot novels featuring the character occurring not more than a couple of millennia after the early-21st century Susan Calvin short stories.

Asimov later integrated the Robot Series into his all-engulfing Foundation series, making R. Daneel Olivaw appear again twenty thousand years later in the age of the Galactic Empire, in sequels and prequels to the original Foundation trilogy ; and in the final book of the Robots series — Robots and Empire — we learn how the worlds that later formed the Empire were settled, and how Earth became radioactive ( which was first mentioned in Pebble in the Sky ).

It was anthologised by Groff Conklin in The Best of Science Fiction, the first of Asimov's stories to have been reprinted, and was later included in The Early Asimov ( in 1972, along with a very brief history of its origins ), The Asimov Chronicles in 1989 and in volume 2 of The Complete Stories in 1992.

Another connection was later established with Robots and Empire, where Asimov revealed how Earth became radioactive, as mentioned in all three novels.

Asimov later integrated them into his all-engulfing Foundation series.

The Three Laws of Robotics ( often shortened to The Three Laws or Three Laws ) are a set of rules devised by the science fiction author Isaac Asimov and later added to.

In later fiction where robots had taken responsibility for government of whole planets and human civilizations, Asimov also added a fourth, or zeroth law, to precede the others:

Three days later Asimov began writing " my own story of a sympathetic and noble robot ", his 14th story.

Several years later Asimov's friend Randall Garrett attributed the Laws to a symbiotic partnership between the two men – a suggestion that Asimov adopted enthusiastically.

In a later essay Asimov points out that analogues of the Laws are implicit in the design of almost all tools:

Asimov took varying positions on whether the Laws were optional: although in his first writings they were simply carefully engineered safeguards, in later stories Asimov stated that they were an inalienable part of the mathematical foundation underlying the positronic brain.

Asimov placed a hint in Foundation's Edge, many years later, that the Eternals might have been responsible for the all-human galaxy ( and the development of humanity on Earth ) of the Foundation Series, but that interpretation is disputed.

While walking down the street in Chicago, Joseph Schwartz, a retired tailor, is the unwitting victim of a nearby nuclear laboratory accident, by means of which he is instantaneously transported tens of thousands of years into the future ( 50, 000 years, by one character's estimate, a figure later retconned by future Asimov works as a " mistake ").

Second Foundation is the third novel published of the Foundation series by Isaac Asimov, and the fifth in the in-universe chronology.

For this reason some commentators, including Isaac Asimov, have suggested that indigo should not be regarded as a color in its own right but merely as a shade of blue or violet.

Isaac Asimov said that the reason Olivaw appeared so often in his books was that his readers and publishers begged it of him.

While Britannicas authors have included writers such as Albert Einstein, Marie Curie, and Leon Trotsky, as well as notable independent encyclopaedists such as Isaac Asimov, some have been criticised for lack of expertise:

Isaac Asimov has also speculated that in the event that he had not been killed while in the service of the British Empire, Moseley might very well have been awarded the Nobel Prize in Physics in 1916, which was not awarded to anyone that year ( along with the prize for Chemistry ).

Earth people are scornful of the Martian colonists, who survive by salvaging " space junk ", yet their way of life suits the Martian colonists for further space exploration, reaching Saturn first and eventually ( Asimov implies ) leading the way to the stars.

Science fiction author and scientist / science writer Isaac Asimov popularized the term in his famous Foundation series of novels, though in his works the term is used fictionally for a mathematical discipline that can be used to predict the general course of future flow.

During World War II, he did aeronautical engineering for the U. S. Navy, also recruiting Isaac Asimov and L. Sprague de Camp to work at the Philadelphia Naval Shipyard in Pennsylvania.

Isaac Asimov, author of the Robot series of books and creator of the Three Laws of Robotics, stated: " Capek's play is, in my own opinion, a terribly bad one, but it is immortal for that one word.

This event prompted Isaac Asimov to say, " John Dalton's records, carefully preserved for a century, were destroyed during the World War II bombing of Manchester.

Asimov used the Roman Empire as the creative basis for the Foundation series, so Trantor is in some sense based on Rome at the height of the Roman Empire.

Shortly before his death in 1992, Asimov approved an outline for three novels ( Caliban, Inferno, Utopia ) by Roger MacBride Allen, set between Robots and Empire and the Empire series, telling the story of the terraforming of the Spacer world Inferno, and about the robot revolution started by creating a " No Law " Robot, and then New Law Robots.

While this earlier script had no direct connections with Asimov, it was considered suitably ' Asimovian ' in nature ( being a locked room mystery with robot suspects ) to provide the basis for an I, Robot movie.

Pebble in the Sky was originally written in the summer of 1947 under the title " Grow Old with Me " for Startling Stories, whose editor Sam Merwin, Jr. had approached Asimov to write a forty thousand word short novel for the magazine.

It was rejected by Startling Stories on the basis that the magazine's emphasis was more on adventure than science-heavy fiction ( despite the editor inviting Asimov to write the latter as an experiment for the magazine ), and again by John W. Campbell, Asimov's usual editor.

During the 1950s Asimov wrote a series of science fiction novels expressly intended for young-adult audiences.

When plans for the television series fell through, Asimov decided to abandon the pretence ; he brought the Three Laws into Lucky Starr and the Moons of Jupiter, noting that this " was a dead giveaway to Paul French's identity for even the most casual reader ".

While the original set of Laws provided inspirations for many stories, Asimov introduced modified versions from time to time.

* Though Isaac Asimov was best known for his long and illustrious career as a science fiction author, his writing came second to his academic career early in his life.

That was followed in 1940 by the Isaac Asimov short story " Robbie ", about a first-generation robot designed to care for children.

During her visit she met with US science fiction editors and also with Isaac Asimov, who granted permission for two of his stories to be adapted on the condition that they could only be shown in the UK – sales to foreign territories were not allowed.

Bradbury was receptive, and by April 7 Asimov was informed that a contract for the novel was in the works.