Can you connect A to A’, B to B’. C to C’ with no lines crossing.
Reveal the solution
Taken from a lecture series on topology and geometry by Dr Tadashi Tokieda of Stanford University.
writing, journalism, books, events, recreation
by philcain
Can you connect A to A’, B to B’. C to C’ with no lines crossing.
Taken from a lecture series on topology and geometry by Dr Tadashi Tokieda of Stanford University.
by philcain
You are in a country surrounded by water and/or impenetrable walls. There are two types of people there, those who always tell the truth and those who always lie. You start walking to the next village when the road splits into two branches. There are two local people standing there. Can you ask a single yes-no question to find out which way to go?
Yes, you can. You can point to one of the branches and ask each person, “Would you say this was the right way?” The non-liar would tell you reliably. The consistent liar, meanwhile, would have to lie in their report about what they would say, so reversing the lie, so telling the truth.
My own solution was clumsier. I’d pointing to one of the branches and ask whether someone from the other group would say yes or no when asked if it was the right way? The liar would have to continue to give the wrong answers, while the truth teller would accurately mimic a liar and give the wrong answer too. So you then just have to do opposite of what they both say.
It is an extension of a similar puzzle with just one liar or non liar, where you can reverse a perpetual liar’s answer by asking, “What would you say if I asked you if you were a liar?” The honest person would say no. But the liar would have to say the opposite of what they would say if asked directly, so telling the truth.
The modelling of real-world liars is simplistic. Real liars are unlikely to feel the need to lie in reporting their own hyperthetical answers, instead they are more likely to lie just as if they had been asked the direct question. Real world liars also have the options of dodging clear questions, by not answering, by giving confusing answers or by giving a clear answer to a different question.
An enterprising liar might ask, “That is an interesting question, but it oversimplies the situation. You might also want to considered the possibility that it might be in the direction you just came from?” Liars don’t lie consistently. Anyone wishing to win people’s trust needs to do so by sticking to a broadly factual basis, expanding this trust on warping accounts in areas which specifically serve them.
by philcain
Q: You have two long planks between which is trapped a load of gunge with a length of one unit (pictured). You then move one plank down one unit and then push it back up again. You repeat this six times. How long is the gunge now?
Moving the plank up from the position shown on the right it will smear the gunge two units up after the first move. And the same thing will happen next time, moving it three units up, and so on. So after six repetitions it will reach seven units up.
by philcain
“What doesn’t kill you makes you stronger,” would be among German philosopher Friedrick Wilhelm Nietzsche’s greatest philosophical hits, but researchers scouring some of his late, unpublished writings say he was working on a follow-up saying.
Notes unearthed from towards the end of his life have revealed that he was having second thoughts, and toying with a number of corollaries to the famous saying, in an unpublished volume of notes called Entschuldigung, auf Nachdenken (Sorry, On Second Thoughts).
Among his amendments to a life’s work was, “What does kill you doesn’t make you stronger.” This is thought to have been the result of ruminating on the likely effects of having tertiary syphilis, a condition that is widely blamed for Nietzsche slipping into madness.
“Later in his life, before he lost his mind to dementia, Nietsche seems to have realised that there may have been different qualities and types of suffering, some of them not beneficial to the sufferer,” says Professor Roger Lithcoe, from the Institute of Nietzsche studies at Heissenbaden.
“He was also toying with a follow up to the famous phrase, but sadly died before they were published.” They never appeared posthumously either, “A series of publishers looked at them but didn’t think they were as catchy as his earlier one.”
“It is a great shame that Nietzsche’s On Second Thoughts did not come into the light sooner, or his earlier saying may not have been used so widely to justify suffering sadism, coercion and neglect, often within educational institutions.”
“We only need to look at ideas like, ‘No pain, no gain’, ‘Tough love’, and the idea that suffering build character to see its ongoing influence,” says Lithcoe. “Nietzsche realised suffering is not necessarily of educational value. Endurance has its uses, but it only teaches us so much.”
In a lucid spell just before his death Nietzscheis said to have commented to a nurse, “Ich habe seit vielen Jahren Syphilis, aber ich habe nichts gelernt,” or, “I have had syphilis for many years, but I have learn nothing from it.”
by philcain
The recent buzz around chatbots should remind us of a human weakness already widely exploited: We readily bond with machines, including the large profit machines known as corporations, often to our detriment.
One technically clued-up journalist this week told of his discomfort at being the target of an attempted seduction by a pre-release version of Microsoft’s new Bing search bot in the New York Times. It is doubtless alarming when silicon gives us the come-on. But we should be uncomfortable too when sense a brand’s personality or a corporation’s kindness.
We put faces on everything like a graffiti artist doodling a smiley on fire hydrants. This urge to personify means we can be readily persuaded to become emotionally engaged with objects and machines, ascribing to them a personhood into which we read personality, motives and morals. It is harmless to see a goofy grin on a fire hydrant, but dangerous when an illusion of personhood is at odds with.
Human intelligence relies on an immensely more complex signal processor than any of our silicon-based chatbots. And our signal processors are deeply embedded in bodies which, in turn, are deeply embedded in the world. No chatbot is ever going to come close to mimicking the output of such an astronomically complex system.
Corporations will not match any personification we make of them either. They exist solely to generate profits for shareholders with no other motive. Even the greediest person does not do that. Employees of corporations, though fully human, are paid to return profit for shareholders, whether or not the method is paralleled by normal human behaviour. Other employees are there to put a human face on it all.
So, while we should not worry that chatbots are getting close to being genuinely comparable with human intelligence, we should be worried we can be persuaded otherwise. We should explore this tendency to personify. It underlies current vulnerabilities to machine romance, notably to branding, public relations, are all charming chatbots attached to profit machines.
We should see machines for what they are, machines, not persons or pseudo persons to either love or to hate, or anything in the middle. These emotions are wasted. Instead we need to know how the machines that serve us operate, where they succeed and where they fail. Knowing this we can decide on rules which would make them work better, rather than how we feel about them.
A hard-headed approach may one day be useful in navigating a world full of charming chatbots. We can warm up by finding ways not to be duped and manipulated by legions of highly sophisticated profit machines. ■
by philcain
Q: You’ve two lengths of fuse, of the kind used for bombs in cartoons. Each will burn for a total of one minute, but burn erratically. Can you use them to measure 45 seconds?
The first step is, as in any decent cartoon, to cackle in an evil way while lighting a match. Then light both ends of one fuse and one end of the other. Once the one burning at both ends is burnt out, light the other end of the remaining half-burnt fuse, cackling.