[8][9][10] Notable Heinlein works include Stranger in a Strange Land,[11] Starship Troopers (which helped mold the space marine and mecha archetypes) and The Moon Is a Harsh Mistress.

[12] His work sometimes had controversial aspects, such as plural marriage in The Moon Is a Harsh Mistress, militarism in Starship Troopers and technologically competent women characters who were formidable,[13] yet often stereotypically feminine—such as Friday.

[34] After his discharge, Heinlein attended a few weeks of graduate classes in mathematics and physics at the University of California, Los Angeles (UCLA), but he soon quit, either because of his ill-health or because of a desire to enter politics.

Beginning in 1970, Heinlein had a series of health crises, broken by strenuous periods of activity in his hobby of stonemasonry: in a private correspondence, he referred to that as his "usual and favorite occupation between books".

[citation needed] At science fiction conventions to receive his autograph, fans would be asked to co-sign with Heinlein a beautifully embellished pledge form he supplied stating that the recipient agrees that they will donate blood.

[3] After For Us, the Living, Heinlein began selling (to magazines) first short stories, then novels, set in a Future History, complete with a time line of significant political, cultural, and technological changes.

There has been speculation that Heinlein's intense obsession with his privacy was due at least in part to the apparent contradiction between his unconventional private life[clarification needed] and his career as an author of books for children.

Red Planet, for example, portrays some subversive themes, including a revolution in which young students are involved; his editor demanded substantial changes in this book's discussion of topics such as the use of weapons by children and the misidentified sex of the Martian character.

Heinlein was always aware of the editorial limitations put in place by the editors of his novels and stories, and while he observed those restrictions on the surface, was often successful in introducing ideas not often seen in other authors' juvenile SF.

"[63] Heinlein decisively ended his juvenile novels with Starship Troopers (1959), a controversial work and his personal riposte to leftists calling for President Dwight D. Eisenhower to stop nuclear testing in 1958.

[67] Heinlein did not publish Stranger in a Strange Land until some time after it was written, and the themes of free love and radical individualism are prominently featured in his long-unpublished first novel, For Us, the Living: A Comedy of Customs.

The Moon Is a Harsh Mistress tells of a war of independence waged by the Lunar penal colonies, with significant comments from a major character, Professor La Paz, regarding the threat posed by government to individual freedom.

The penultimate novel of this period, I Will Fear No Evil, is according to critic James Gifford "almost universally regarded as a literary failure"[69] and he attributes its shortcomings to Heinlein's near-death from peritonitis.

[88] Brian Doherty cites William Patterson, saying that the best way to gain an understanding of Heinlein is as a "full-service iconoclast, the unique individual who decides that things do not have to be, and won't continue, as they are".

In it, Heinlein broke with the normal trends, stating that he believed in his neighbors (some of whom he named and described), community, and towns across America that share the same sense of good will and intentions as his own, going on to apply this same philosophy to the US, and humanity in general.

[26] When Robert A. Heinlein opened his Colorado Springs newspaper on April 5, 1958, he read a full-page ad demanding that the Eisenhower Administration stop testing nuclear weapons.

He called for the formation of the Patrick Henry League and spent the next several weeks writing and publishing his own polemic that lambasted "Communist-line goals concealed in idealistic-sounding nonsense" and urged Americans not to become "soft-headed".

[106] Heinlein summed up his attitude toward people of any race in his essay "Our Noble, Essential Decency" thus: And finally, I believe in my whole race—yellow, white, black, red, brown—in the honesty, courage, intelligence, durability, and goodness of the overwhelming majority of my brothers and sisters everywhere on this planet.

[109] A common theme in Heinlein's writing is his frequent use of the "competent man", a stock character who exhibits a very wide range of abilities and knowledge, making him a form of polymath.

[110] While Heinlein was not the first to use such a character type, the heroes and heroines of his fiction (with Jubal Harshaw being a prime example) generally have a wide range of abilities, and one of Heinlein's characters, Lazarus Long, gives a wide summary of requirements: A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly.

It is disconcerting, for example, that in Expanded Universe Heinlein calls for a society where all lawyers and politicians are women, essentially on the grounds that they possess a mysterious feminine practicality that men cannot duplicate.

For example, in Time Enough for Love Heinlein describes a brother and sister (Joe and Llita) who were mirror twins, being complementary diploids with entirely disjoint genomes, and thus not at increased risk for unfavorable gene duplication due to consanguinity.

Many of his stories, such as Gulf, If This Goes On—, and Stranger in a Strange Land, depend strongly on the premise, related to the well-known Sapir–Whorf hypothesis, that by using a correctly designed language, one can change or improve oneself mentally, or even realize untapped potential (as in the case of Joe in Gulf—whose last name may be Greene, Gilead or Briggs).

On that theme, the phrase "pay it forward", though it was already in occasional use as a quotation, was popularized by Robert A. Heinlein in his book Between Planets,[120] published in 1951: The banker reached into the folds of his gown, pulled out a single credit note.

He was at the top of his form during, and himself helped to initiate, the trend toward social science fiction, which went along with a general maturing of the genre away from space opera to a more literary approach touching on such adult issues as politics and human sexuality.

For example, when writing about fictional worlds, previous authors were often limited by the reader's existing knowledge of a typical "space opera" setting, leading to a relatively low creativity level: The same starships, death rays, and horrifying rubbery aliens becoming ubiquitous.

[citation needed] But Heinlein utilized a technique called "indirect exposition", perhaps first introduced by Rudyard Kipling in his own science fiction venture, the Aerial Board of Control stories.

[128] Likewise, Heinlein's name is often associated with the competent hero, a character archetype who, though he or she may have flaws and limitations, is a strong, accomplished person able to overcome any soluble problem set in their path.

Scores of science fiction writers from the prewar Golden Age through the present day loudly and enthusiastically credit Heinlein for blazing the trails of their own careers, and shaping their styles and stories.Heinlein gave Larry Niven and Jerry Pournelle extensive advice on a draft manuscript of The Mote in God's Eye.

"[141] Heinlein has inspired many transformational figures in business and technology including Lee Felsenstein, the designer of the first mass-produced portable computer,[142] Marc Andreessen,[143] co-author of the first widely-used web browser, and Elon Musk, CEO of Tesla and founder of SpaceX.