Quotes from David Boyle

Meanwhile, the War Office cryptographers at MI1(b) were also gearing up, though we know less about their activities because all their records were destroyed at the end of the war, under retired Brigadier General Francis Anderson, a mathematician who had been in charge of tapping Boer telegrams during the South African war.

Turing's report left these questions hanging, but he did suggest a forerunner of what would eventually become the Turing Test: if you played chess against a learning machine, would you know if it was a human being or a computer?

It was pretty clear, once the SKM codebook was in British hands, that the signals were not just coded but also enciphered. Codes substitute whole phrases with numbers or letters. The German navy then added an extra layer using a cipher for each number, so that each one stood for something else, using another key that the Room 40 team clearly did not possess.

Later in the war, the German naval cipher would be changed every day at midnight, and it was the duty of the night duty team to crack it before daybreak. But that was some years ahead.

What if there was some kind of machine capable of working out the Entscheidnugsproblem? This was the germ of the idea that eventually became a computer, but no such thing existed at the time.

In fact, by the end of the war, 20,000 wireless signals had poured into Room 40 and most of them were successfully decoded.

But Hall was not stopping there. The next stage was for him and Drake to send false reports back, using the names of spies who had actually been arrested – a technique that was perfected in the Second World War – to give the impression that they had uncovered military preparations to invade the German coast in Schleswig-Holstein. The purpose was to force the enemy fleet out to defend their coast.

You shall not put people to death lazily, because of who they are.' 'We

As well as the fears about fifth columnists and German refugees that obsessed the nation – largely without foundation, as it turned out – there was some accurate and unnerving reporting from France. "The threat to this island grows nearer and nearer," said the Daily Express. "While the people of Britain wait anxiously for news of their soldiers over the Channel, they must prepare for the onslaught which may come upon their own soil.

Turing believes machines think. Turing lies with men. Therefore machines cannot think.

But the campaigners wanted more than just an apology; they wanted a proper pardon. The government refused on the grounds that it would set a precedent, even though pardons had recently been given to 18 former terrorists under the Northern Ireland Agreement

On the other hand, he did make a big step towards the practical creation of a Turing machine by proposing that the binary system should be used, once again based on the kind of punchcards

To pass the Turing Test the computer would have to do more than imitate. It would have to be a learning entity.

The historian Hugh Trevor Roper, who visited often, described the atmosphere as 'friendly informality verging on apparent anarchy'. One military policeman famously mistook Bletchley for a military asylum. Turing

While the first ships were arriving in Dunkirk, Churchill and the war cabinet were meeting for the third time that day, and his own struggle with his Foreign Secretary was now joined: they disagreed about whether Hitler's terms, offered through the Italians, would be outrageous or not. Churchill said they would be worthless. He didn't feel strong enough to oppose him outright, and tried to delay a decision until they knew what was happening in Dunkirk.

I desire the company of a man who could sympathize with me, whose eyes would reply to mine... gentle yet courageous, possessed, has a cultivated as well as a capacious mind, whose tastes are like my own to approve or amend my plans.' Mary Shelley, Frankenstein, 1819

All Cretans are liars, as a Cretan poet once told me.

Natural Wonders Every Child Should Know by Edwin Tenney Brewster.

Men wrote the Bible, but God made our consciences.

Men wrote the Bible, but God made our consciences. Does he want them to gather dust?' There

To make matters worse, the British sighted French tanks, thought they were German and attacked them. The German commander charged with the task of resisting was a man who would soon be the most famous German general of them all, then known as Major-General Erwin Rommel. By 6pm, Rommel had prevailed, the attack was over and the remaining British tanks – and most of the commanders had been killed – were in retreat

Since 1941, according to his biographer Andrew Hodges, Turing had been watching his proto-computers and decided that originality and intuition were processes that could be computed.

One of the most famous paradoxes ever articulated is often known by the title 'the liar's paradox'. At its simplest you can express it just by saying: 'I am lying'. The liar's paradox is a complicated business, discombobulating to think about because after all, if I'm lying, then my statement 'I am lying' must itself be a lie, unless I was actually telling the truth, in which case I would have been telling a lie.

out a calculation or apply an algorithm. Next