A machine can now not only beat you at chess, it can also outperform you in debate. Last week, in a public debate in San Francisco, a software program called Project Debater beat its human opponents, including Noa Ovadia, Israel's former national debating champion.

Brilliant though it is, Project Debater has some weaknesses. It takes sentences from its library of documents and prebuilt arguments and strings them together. This can lead to the kinds of errors no human would make. Such wrinkles will no doubt be ironed out, yet they also point to a fundamental problem. As Kristian Hammond, professor of electrical engineering and computer science at Northwestern University, put it: "There's never a stage at which the system knows what it's talking about."

What Hammond is referring to is the question of meaning, and meaning is central to what distinguishes the least intelligent of humans from the most intelligent of machines. A computer works with symbols. Its program specifies a set of rules to transform one string of symbols into another. But it does not specify what those symbols mean. Indeed, to a computer, meaning is irrelevant. Humans, in thinking, talking, reading and writing, also work with symbols. But for humans, meaning is everything. When we communicate, we communicate meaning. What matters is not just the outside of a string of symbols, but the inside too, not just how they are arranged but what they mean.

Meaning emerges through a process of social interaction, not of computation, interaction that shapes the content of the symbols in our heads. The rules that assign meaning lie not just inside our heads, but also outside, in society, in social memory, social conventions and social relations. It is this that distinguishes humans from machines. And that's why, however astonishing Project Debater may seem, the tradition that began with Socrates and Confucius will not end with artificial intelligence.

When almost everyone has a mobile phone, why are more than half of Australian homes still paying for a landline (座机)

These days you'd be hard pressed to find anyone in Australia over the age of 15 who doesn't own a mobile phone. In fact plenty of younger kids have one in their pocket. Practically everyone can make and receive calls anywhere, anytime.

Still, 55 percent of Australians have a landline phone at home and only just over a quarter （29%） rely only on their smartphones, according to a survey （调查）.Of those Australians who still have a landline, a third concede that it's not really necessary and they're keeping it as a security blanket —19 percent say they never use it while a further 13 percent keep it in case of emergencies. I think my home falls into that category.

More than half of Australian homes are still choosing to stick with their home phone. Age is naturally a factor （因素）-only 58 percent of Generation Ys still use landlines now and then, compared to 84 percent of Baby Boomers who've perhaps had the same home number for 50 years. Age isn't the only factor; I'd say it's also to do with the makeup of your household.

Generation Xers with young families, like my wife and I, can still find it convenient to have a home phone rather than providing a mobile phone for every family member. That said, to be honest the only people who ever ring our home phone are our Baby Boomers parents, to the point where we play a game and guess who is calling before we pick up the phone （using Caller ID would take the fun out of it）.

How attached are you to your landline? How long until they go the way of gas street lamps and morning milk deliveries?

By day, Robert Titterton is a lawyer. In his spare though he goes on stage beside pianist Maria Raspopova — not as a musician but as her page turner. "I'm not a trained musician, but I've learnt to read music so I can help Maria in her performance."

Mr Titterton is chairman of the Omega Ensemble but has been the group's official page turner for the past four years. His job is to sit beside the pianist and turn the pages of the score so the musician doesn't have to break the flow of sound by doing it themselves. He said he became just as nervous as those playing instruments on stage.

"A lot of skills are needed for the job. You have to make sure you don't turn two pages at once and make sure you find the repeats in the music  when you have to go back to the right spot." Mr Titterton explained.

Being a page turner requires plenty of practice. Some pieces of music can go for 40 minutes and require up to 50 page turns, including back turns for repeat passages. Silent onstage communication is key, and each pianist has their own style of "nodding" to indicate a page turn which they need to practise with their page turner.

But like all performances, there are moments when things go wrong. "I was turning the page to get ready for the next page, but the draft wind from the turn caused the spare pages to fall off the stand," Mr Titterton said, "Luckily I was able to catch them and put them back."

Most page turners are piano students or up-and-coming concert pianists, although Ms Raspopova has once asked her husband to  help her out on stage.

"My husband is the worst page turner," she laughed. "He's interested in the music, feeling every note, and I have to say: 'Turn, turn!' "Robert is the best page turner I've had in my entire life."