Alan Turing: born 1912, died 1954, resurrected 2013

It’s tempting to view Alan Turing as Britain’s analogue to America’s J. Robert Oppenheimer. Two certified scientific war heroes of the ‘40s, pilloried by their governments in the ‘50s for supposed offenses totally unrelated to their wartime service, in spectacular outbursts of ingratitude.

The differences outweigh the similarities, however. Oppenheimer’s purported offense was strictly political: his refusal to support development of the H-bomb won him the enmity of Atomic Energy Commission Chairman Lewis L. Strauss, who humiliated him with ginned-up accusations of disloyalty, knowing how explosive the charges would be in the Red Scare atmosphere of the time.

But Oppenheimer kept the support of a large cadre of fellow physicists--Isidor I. Rabi, for one, ridiculed the loyalty committee members to their faces by reminding them of Oppie’s role in bringing the Manhattan Project to its successful conclusion: “We have an A-bomb…and what more do you want, mermaids?” And his public rehabilitation came during his lifetime, when John F. Kennedy awarded him the government’s Enrico Fermi Prize ($50,000 and a medal for public service).

Fortune did not so bestow its apologies on Alan Turing, who was granted a royal pardon on Christmas Eve for his 1952 conviction for “gross indecency”--read homosexuality. The pardon comes 59 years after Turing’s suicide.

The spate of obituary-like profiles of the outstanding mathematician and computing pioneer that have appeared over the last week have outlined his numerous achievements.

These start with his definition of computable numbers and his devising of the “Turing machine” in 1936--foundations of modern computer science--and his leadership of the cryptanalysis effort that broke the Nazis’ Enigma code in 1939-42, which saved thousands of Allied lives and preserved tons of desperately needed oceangoing cargo. The “Turing Test,” which is popularly taken to mark when a machine can “out-think” a human but is far more complex than that, and far more interesting, is often viewed as a foundation of the science of artificial intelligence.

Andrew Hodges’ 1983 book “Alan Turing: The Enigma,” is the indispensable guide to Turing’s life and work and one of the finest biographies of a scientific genius ever written. On a more personal basis one can turn to the appreciation of Turing written this year by the computer scientist and social critic Jaron Lanier, which appears here. “I couldn’t owe him more,” Lanier writes.

Lanier’s essay appeared last summer, when it first became known that the British government was thinking of issuing a posthumous pardon to Turing for his prosecution and conviction in 1952 for “gross indecency” under a law dating from 1885.

Turing’s crime of homosexuality was punished at a moment when the hypocrisy of the British ruling class was reaching its apogee. He was given the opportunity of choosing between prison and “organotherapy,” or chemical castration through the application of female hormones to reduce his sexual urges. Devoted to his work and the life of the mind, he chose the latter, for prison would have interfered with his work and led to the loss of his job at Manchester University and access to its computer.

“He had the choice between his body and feelings on the one hand, and his intellectual life on the other,” Hodges observes. “It was a remarkable decision problem. He chose ‘thinking’ and sacrificed ‘feeling.’”

Two years later, and a full year after the chemical therapy had ended, he committed suicide. One of his closest friends wrote that “because his main interests were in things and ideas rather than in people, he was often alone. But he craved for affection and companionship.” Hodges adds: “He was more alone than anyone could ever see.”

The pardon is the product of years of campaigning by the LGBT community, along with prominent scientists such as Stephen Hawking. Former Prime Minister Gordon Brown in September urged “this recognition of Alan’s status as one of Britain’s most famous victims of homophobia (as) another step towards equality, and long overdue.”

But the royal act raises discomfiting questions about what a pardon means, coming six decades late. Can it wipe the slate clean? Or is it, as Lanier says, “nothing but dust and posturing”? The question boils down to whether a society learns anything from the embarrassment of righting a wrong after six decades. Given the hypocritical treatment still imposed by society today on disadvantaged communities--LGBT, black, Latino, poor--what pardons will we be asking posterity to grant us?