The Roger Bacon of legend was an alchemist and sorcerer who could materialise a bridge out of thin air so that he and his retinue could cross the Channel at leisure.
He also constructed a mirror that could be used to observe any place on earth. This was smashed on the orders of the authorities at Oxford University, worried that students were spending too much time spying on people rather than studying. The tale sprang from the Franciscan friar’s experiments with lenses and his invention of the magnifying glass, but the novelty of this work allowed such fantastical exaggerations to seem plausible.
Bacon’s thought and learning spanned the ancient and medieval worlds, the Christian and the Islamic. He was one of the first Westerners to open the Muslim seed bank of ideas and, with his teacher Robert Grosseteste, can claim to be the first experimental scientist.
The legend was not to last. Bertrand Russell wrote in his History of Western Philosophy that Bacon had been praised “far beyond his deserts”. If so then the friar has lately received his comeuppance, not featuring at all in the most respected history of philosophy since Russell’s — Anthony Gottlieb’s The Dream of Reason. The anniversary of Bacon’s death passed with little notice in 1994, and two years later the publishers of The Cambridge Companion to Bacon were confident that no one would be confused when the cover of their book about Francis Bacon did not specify a Christian name.