Brilliant science fiction can ignite scientific ambition. After the death of Ray Bradbury on 5 June, thousands of researchers must have reflected on the inspirational power of his works. The author of The Martian Chronicles (1950), The Illustrated Man (1951) and Fahrenheit 451 (1953) died in Los Angeles at the age of 91, ruminating and planning stories until the end.

Ray Bradbury helped to relaunch science fiction as art form. Credit: T. KORODY/SYGMA/CORBIS

Bradbury was the last living member of the 'BACH quartet' — made up of himself, Isaac Asimov, Arthur C. Clarke and Robert Heinlein. In the 1950s and 1960s these men pulled science fiction from its pulp-magazine ghetto into the hardcover best-seller lists. Asimov, Clarke and Heinlein helped to shatter barriers, establishing the legitimacy of literature that explores plausible tomorrows. But it was Bradbury who made clear to everyone that science fiction can be an art form combining boldness and broad horizons with beauty.

Often, when an author of future-oriented fiction achieves mainstream literary acclaim, there is a temptation to announce, “I don't write sci-fi,” as if dropping the label will ensure escape from the ghetto. But when Bradbury said that, he meant the opposite. He wrote mostly fantasy, horror and suspense because, he once told me, “I can't do science, but that's my loss.” He never learned to drive and for most of his life avoided aeroplanes, but Bradbury's works had a major influence on space travel and exploration. He became a fixture on television, interviewed whenever some epochal milestone — such as the first Moon landing — was achieved.

In his 1950 breakthrough anthology, The Martian Chronicles, rocket ships are taken for granted. The book omits any technical details. The rockets are simply marvellous conveyances that deliver the characters to a frontier where awe mixes with terror and unquenchable hope. Bradbury's doomed Martians are more than just surrogates for native, colonized peoples. They are also humanity's complex and flawed elder siblings on the ladder of wisdom, instructing in spite of their fatal errors. Readers loved the rockets, but the characters taught us about balance and cost.

Bradbury's great novel, Fahrenheit 451, took up a very different tradition: the self-preventing prophecy. The author wrought a tale of book-burning and political correctness gone wild that filled readers first with shock, then with determination to thwart that possible future. He thus joined the ranks of authors such as George Orwell, whose Nineteen Eighty-four (1949) and other works frightened millions into taking action through politics and daily life. Again, it was not futuristic technology that made Fahrenheit 451 effective. The book is, instead, a potent example of what Albert Einstein called the Gedankenexperiment, or thought experiment — the essence of good science fiction.

Ray Douglas Bradbury was born in 1920, in Illinois. When he was 13, his family moved to Los Angeles, California, where he remained for the rest of his life. Among many early influences on a fertile young imagination was the fact — very exciting to a child — that one of his ancestresses had been tried as a witch in Salem, Massachusetts, in the late seventeenth century. He often described the lasting impressions left by the films of early-twentieth-century horror actor Lon Chaney Senior, and the occasion when a stage magician shocked Bradbury's nose with an electric sword, commanding him to “live forever!” A child of the Depression, Bradbury nurtured his love of writing in free public libraries and while hawking newspapers on street corners.

Like many authors who followed, Bradbury started out writing stories for mimeographed fan publications of the 1940s, climbing gradually upwards while honing his craft. His skills later took him to Hollywood, where he scripted films such as John Huston's Moby Dick (1956) and the US television series Ray Bradbury Theater (1985–92), while raising four daughters and penning one luminous book after another.

Bradbury's stories and novels often plunged into dark themes. There is satanic-huckster villainy in Something Wicked This Way Comes (1962), and the 1954 short story All Summer in a Day starkly reveals how basic the tendency toward cruelty is, and that childhood is neither pure nor innocent. His scientific readers forgave things such as his water-drenched Venus and untechnological plot-drivers, including monsters and childhood terrors under the bed.

Could anyone reconcile this chain of chillers with Bradbury's self-proclaimed optimism? He himself did. Human beings are fretful creatures, he said. Our worries often cause us to shine light in dismal corners, and thus help us to do better. To be better.

In fact, Bradbury had a lot to say about a human trait he despised: cynicism. His word for it was treason. Treason against a world — and humanity — that had, in his view, improved enormously over the course of a generation in terms of technological achievements, and in ethics and behaviour. The racism, sexism and class prejudice that our ancestors took for granted may not have been eliminated, but society had at least succeeded in pushing them into ignominy.

Ray Bradbury's writing danced along the boundaries between mystery, sci-fi, horror and fantasy. What mattered to him most was the direction we are heading: forwards, propelled by ever-growing knowledge and the will to peer even farther.