The majority of strings can not be compressed. By string I just mean a binary number, which is ultimately what all computerised stuff is.
How come? Well, say you wanted to compress a 4-bit string to a 3-bit string. There are 24 possible 4-bit strings, but only 23 possible 3-bit strings: there are twice as many possible 4-bit strings as 3-bit ones.
Compression is a lossless process so that the compression can be reversed, so each uncompressed (4-bit) string should match up with a unique compressed (3-bit) string, in a one-to-one correspondance. Yet there are only half as many 3-bit possible strings as 4-bit ones, meaning that only half of the 4-bit strings can be compressed. Bear in mind, this is just for compressing a string by a single bit. If you want to remove another bit, the possibilities half yet again, and so on.
I think that’s pretty cool.
I’d like to learn more about compression. I realise that a lot of compression is achieved just by removing irrelevant zeroes, but that’s about as far as my knowledge goes.
The big BBC science series on at the moment is “Wonders of the Solar System“, presented by Brian Cox. It’s a series of 5 hour-long documentaries, focusing on the Solar System and Earth’s place in it.
I’ve been disappointed with Horizon recently – I think it’s intent on dramatising science and stirring up false controversy whilst deliberately trying to confuse viewers – and it’s a relief to finally have some documentaries done properly. As long as Brian’s Mancunian accent and perma-smile don’t put you off, you’re in for a treat: it’s simple (whilst remaining interesting) and clear, and it features some absolutely beautiful imagery of the Earth, the Solar System, and the surrounding stars in the Milky Way. ((Much of it is well explained by the program, there’s not much gratuitous beauty.))
Wonders occasionally reminds me of Carl Sagan‘s epic series “Cosmos: A Personal Voyage” ((I actually think Wonders has one or two deliberate homages to the music of Cosmos.)). It wouldn’t be fair to compare the two (Wonders is only about the Solar System, whereas Cosmos is about everything ((Hence the title.))) but I feel they both achieve something which many other documentaries don’t: inspiration. I think that’s the most important aspect of a documentary, especially for the children who are watching.
Each of the episodes has a particular and mostly separate focus, hinted at by the titles:
- Empire of the Sun
- Order Out of Chaos
- The Thin Blue Line
- Dead or Alive
- Aliens
Empire of the Sun
Of all the objects in the Solar System, and perhaps the Universe, I am awed most by the Sun. Only by the Sun’s energy were we born and do we continue to survive. Its power is incomprehensible: we can feel the warmth on our skin, 150 million kilometers away.
Above is a picture from the episode ((All of these pictures have been taken from the BBC’s website. I hope they don’t mind.)), showing the Aurora Borealis: bits of Sun raining down along the Earth’s magnetic field lines. The episode also features an eclipse: in my opinion, the most awesome sight there is. I witnessed a partial solar eclipse in August 1999. I’ll never forget that image of the nearly-concealed Sun which I saw through a stack of old sunglasses.
This episode was a great start to the series.
In the second episode, Brian explains how the laws of physics are the same all across the universe, so phenomena on Earth also occurs on other planets: crater, storms, tornadoes, ice. He even went storm chasing, but unfortunately he didn’t catch anything: it’s a good job they had some stock footage lined up instead.
I so want to see a tornado some day.
The third episode is about Earth’s atmosphere. I’ve known about this one for a long time, because I follow Brian on Twitter and he was very excited during filming. In it, he flies in an English Electric Lightning to the edge of space. Although Brian seems to be in love with the aeroplane, it’s true: it’s a magnificent piece of engineering ((The plane that he flew in was destroyed shortly afterwards in a crash. You got lucky there mate.)).
The ending also particularly stood out: it’s about one of Saturn’s moons, Titan ((Brian always said Saturn with emphasis on the “ur”, as if he’s saying “sah-turrrn” and I’ve never heard it pronounced like that before. I pronounce it with emphasis on the first syllable: “sah-tun”. Is there a right way and a wrong way?)). A world like our own in some ways, with lakes and clouds and rain. But the lakes are of liquid methane, and the rain falls in huge drops at the speed of snowflakes, and the temperature is hundreds of degrees cooler than on Earth.
It’s amazing that we know all this.
The fourth episode, which I watched this afternoon, is about why the Earth is a living planet, and the rest of the Solar System is dead. The answer is mainly due to our size and distance from the Sun, as well as the effect of Jupiter’s gravity on nearby asteroids. It’s all information that I was familiar with, but the presentation was fresh and I didn’t get bored. Quite the opposite, actually, and I thought that the view from up Mauna Kea of the rolling clouds at sunset was just beautiful. Extraordinary. That’s another place I’d like to visit.
The final episode, Aliens, airs on Sunday. I hope Brian can full convey his wonder at the possibility – probability! – of the existence of extra-terrestrial life. I look forward to it.
With the high quality of the series, and assuming it has been a success, I’m sure Brian will be back for another BBC documentary series. I hope so.
UPDATE: Aliens was pretty good too, the main ‘Wonder’ being about Europa, with its huge sub-surface water oceans being possible havens for life. Brian will be making a follow-up series with the same team, called “Universal” “Wonders of the Universe” for broadcast next year.
After writing my previous post, called “Legal Tender“, I got a reply from a slightly upset George ((It started with the line “WILFRED WILSON, you have misquoted me massively!”)). I confess, my memory was faultly, and I prepended an explanatory paragraph to the post to make George’s arguments clear. He was not arguing that Scottish bank notes are legal tender; rather, he was more concerned that the English refusing to accept Scottish money constitutes discrimination.
It’s an issue that I didn’t explore in my first post, but I shall do so here, in response to George’s email:
I did maintain that it would be discrimination if you were to reject Scottish banknotes as payment, and I still think that that is the case. In the same way as it would be discrimination to reject English banknotes if you were in Scotland […]
The concern is whether or not it would be acceptable to reject Scottish banknotes if it took your fancy. You seem to think that it’s okay for any shopkeeper to refuse payment at any time, irrespective of whatever reason. If I understand you, you’re arguing that it’s not discrimination because you’re drawing the distinction between the money, and not necessarily the people. But the majority of people who use Scottish money are Scottish people, and the note is inextricably linked with Scottish identity and culture.
Imagine, for instance, the racist shopkeeper: racism obviously is criminal.
As an aside: by your logic, and by your legal evidence (that shopkeepers are able to refuse any transactions at the point of sale) then racist shopkeepers should be able to simply reject any business with black people whatever notes they use.
Anyway, imagine if there was printed a banknote with, say Nelson Mandela on it, or a picture of a gay pride rally. Imagine any such banknote that is culturally symbolic and linked with the identity of any other group against which discrimination is possible and likely. This is a suitable analogy I’m sure you’ll agree. By your understanding of the situation, any shopkeepers should be able to reject this note in exactly the same way they would reject a Scottish note. I argue that this would be discrimination.
(I should say that we’re assuming shopkeepers aren’t rejecting it because they think it’s forged or unusable or some other valid reason). [Wilf: agreed]
It’s quite the interesting debate in any case.
You’re right George, it is interesting.
When George and I were discussing this on the pier at St Andrews, I wasn’t concerned with right and wrong, but whether it was legal or illegal. I didn’t make that clear, but neither did George – his use of the word ‘discrimination’, as well as comparisons to racial discrimination, as in his email here, made me think that he was arguing that it was illegal ((Hence my dismissal of the idea as “ridiculous” in my previous post.)).
To use discrimination in its loosest terms, the different treatment of two things, then of course it’s discrimination to accept English money but not Scottish money ((Just as it’s discrimination to make males use one bathroom and females use another.)). It is discrimination by definition, but that’s to say nothing of its legality, its rightness or even its fairness.
Therefore, the first thing I had to do was to clarify just what George meant by discrimination: does he think it’s criminal, morally wrong, or just unfair?
George replied:
I’d avoid “morally wrong” because it’s not particularly high on a list of moral sins, and I’m sure there isn’t much malicious intent behind it most of the time, but I do believe it is unfair.
You know what? After all that discussion ((which, admittedly, was probably just a couple of minutes long.)), it seems we agree. We’d been arguing based on different definitions of “discrimination”. Yes, I think it’s unfair that I have to be conscious of retaining English notes for use in England, in case my Scottish notes are rejected ((Sadly, fairness doesn’t seem have any standing in this world.)).
Is that where the argument ends? That argument, yes, but I wonder: should it be illegal to reject Scottish notes?
(Just to make it clear: it is legal to reject Scottish bank notes, and that is what I was originally arguing. In fact it’s always legal to reject Scottish notes, at least in England and Wales – to respond to “the concern is whether or not it would be acceptable to reject Scottish banknotes if it took your fancy”: yes it is legally acceptable).
Regarding racism: I realise that racially discriminating in the provision of goods and services is illegal, meaning that you can’t refuse to do custom with a black person because of that person’s skin colour – that’s due to the Race Relations Act. Currently, discriminating against Scottish notes is not considered criminal discrimination against the Scottish ‘race’.
Perhaps there could possibly be a situation where a whole racial/other-discriminatable-against group is solely represented by a different version of a common currency, perhaps with black people in South Africa or something, but I don’t think such a scenario exists and the situation discussed here definitely does not fit this ((In my opinion, that is.)).
In my opinion, it would be wrong to force shop keepers to accept Scottish bank notes; no shop keepers are forced to accept English notes (although I’ve never heard of anyone rejecting them), so they shouldn’t be forced to accept Scottish ones. However, some MPs have proposed forcing traders to accept Scottish notes if they accept English ones as well, and this would be the more realistic proposal. The end is effectively the same, but with a different means.
I’m all for allowing businesses the freedom to run as they please, with limits to protect the public. Perhaps a legal requirement should happen, not because it would be racist otherwise, but just to make things easier ((I think it would be even easier to scrap Scottish money, but I don’t think that’s going to happen.)).
Thankfully this will not be an issue in the near-future as we move away from physical money to a completely digital world.
UPDATE: George informed me that I “have misquoted me massively”, and on further remembrance, I think he’s right. George was not arguing that Scottish bank notes were legal tender, although he does maintain that the rejection of Scottish notes in England is (unfair) discrimination. However, I’m going to leave this article as it is, because its purpose isn’t to point and laugh at George, instead it is an explanation of the term ‘legal tender’. The story just serves as a bit of fun. Now let’s return to the original article.
The topic of legal tender came up when I was talking to George at the St Andrews Open Day last Wednesday.
When I’m in England, I told him, I use English bank notes ((At least I think this is how the topic came up.)). When I return to Scotland, I keep my remaining English notes in reserve, spending any Scottish notes before my English ones. I get the feeling that English notes are more ‘proper’: they’re universally accepted, whereas some English shops are suspicious of Scottish notes. That’s why I hold on to them.
“It doesn’t matter,” said George. “It’s all legal tender.”
Hmm, I wasn’t so sure. Firstly, I knew that Scottish notes were issued by different private banks (RBS, HBOS, Clydesdale Bank) ((Who gets to choose how much money to print?)) whereas English notes are all printed by the Bank of England. Perhaps there are more differences. Secondly, I realised I didn’t even know what the term ‘legal tender’ meant ((I wonder how many other words I think I know, but which I’ll find out mean something else?)). How could I know whether a car is mauve or not if I don’t know what colour mauve is?
“What does that even mean George?”
“Well, that you have to accept Scottish notes as payment if you’re selling something.”
This sounded stupid to me: since when were traders forced to sell anything? Surely it’s at a seller’s discretion whether or not to do business with a particular person. That makes sense, right?
“It’s discrimination,” he said.
“Haha. What?!”
“It discrimination against Scottish people.”
Oh God! I told him that he was ridiculous and I’d look it up when I get home ((Still on my iPod Touch, and there’s no Wi-Fi at the end of piers :(.)). I did. From Wikipedia ((Yes, I’m using Wikipedia as my source, but it’s reliable and it seems well sourced (not that I can be bothered following the citations, I trust Wikipedia).)):
Legal tender or forced tender is an offered payment that, by law, cannot be refused in settlement of a debt, and have the debt remain in force.
Ah right, that’s what legal tender is. If one person is in a debt to the another, the creditor must accpet legal tender as payment of that debt from the debtor. That’s it.
I’d heard the phrase several times and my assumed definition (‘genuine money’) seemed to make sense. Apparently not ((Maybe those who use the term don’t know what it actually means, either.)). Whenever I hear the phrase ‘legal tender’, I think of one of Michael McIntyre’s stories from “Live at the Apollo”, about a Scottish man trying to buy something in England with Scottish notes: “I think you’ll find pal, that’s legal tender” ((Imagine that, said in a really thick Glaswegian accent.)). As it turns out:
Scottish and Northern Ireland banknotes are not legal tender anywhere
Oh. And even if money is legal tender, it doesn’t have to be accepted as payment:
Traders may […] choose not to accept banknotes as payment as contract law across the United Kingdom allows parties not to engage in a transaction at the point of payment if they choose not to.
In fact, in Scotland and Northern Island no paper money is legal tender; in England and Wales only English notes are. Not that the status of money as legal tender is ever something that most people will need to know or worry about.
P.S. I thought this was interesting too:
Currently, 20 pence pieces and 50-pence pieces are legal tender in amounts up to 10 pounds; 5-pence pieces and 10-pence pieces are legal tender in amounts up to 5 pounds; and 1-penny pieces and 2-pence pieces are legal tender in amounts up to 20 pence.
I’d guess most creditors would reluctantly accept a sack of coppers as payment for a debt, but they wouldn’t have to ((Although they might have to in Scotland, as “Scots law requires any reasonable offer for settlement of a debt to be accepted.”)).
I’ve had some thoughts about technology and change bouncing around my head for quite a while now.
I think it started when I read one of Scott Simpson‘s posts, “That Essay Would Have Been Terrible Anyway“:
“A friend is going through a tough time right now. Last night I consoled him and offered advice, while simultaneously browsing for a new camera case on my iPhone.
It occured to me to write a long essay about how that scenario points to the increasing fragmentation of our attention and the threat that technology poses to real-world relationships. But really it just means I’m an asshole.”
Scott’s a pretty funny guy, and he’s right, of course. Whether or not he thinks “that essay would have been terrible” because it would have been wrong or because it would have been plain boring – I don’t know, but it’s still a dickish thing to not give a friend your full attention when they really need it.
It was the idea of technology being a bad thing ((I’m not saying that Scott believes this, judging by his type of humour and the title of his post.)) that got me thinking. I’m not convinced that the internet, and particularly the rise of social websites like Facebook, is posing a threat to real-world relationships, and I’m not convinced that they’re increasing the fragmentation of our attention (which I’m not even convinced would be a bad thing).
- The internet allows people to connect more, to keep in touch with more friends who live in more locations than would be otherwise possible.
- One could argue that that would lead to more superficial relationships, but that is not a requirement of using social networks, just a possibility.
- People argue that people who use social networks see their friends face-to-face less often, leading to problems of isolation. Again, it’s not necessary to have less real-world socialising as a consequence of social networking, even though some people may choose to do this.
The effect of the internet on one’s social life depends on how one uses it, and with what attitude. Ultimately it’s one’s own choice whether or not one makes the effort to see friends in person – the internet doesn’t prevent socialising, it helps it: people who don’t want to be social in real life just aren’t going to be. Sadly, the internet ends up as the scapegoat.
As for our attention becoming more and more fragmented; is that what’s meant by doing lots of things at once? Isn’t that a skill? Sure, some people are addicted to checking their email and can’t focus on work when there’s a world of possibilities at their fingertips. That’s not the internet’s fault: it’s the person’s fault for not being more disciplined and not learning how to control their impulses. Maybe it’s something that we could be taught at school: how to avoid distractions, such as the internet, when we’re doing something important.
Scott’s right. People who do things like that are assholes. But it’s not technology’s fault.
I thought some more.
Before properly writing my speech to Perth Speakers’ Club, I jotted down some ideas in a notebook. I noticed that my handwriting looked rather weird – it could have been down to writing whilst in bed, but I thought there was something more, so I wrote this:
I thought that my handwriting had gone awful but I just needed something to lean on. Then again, after barely handwriting for 8 months (wow), it has changed. I can type reliably at about 100 wpm, yet I handwrite so much slower.
I’m used to being able to get text down almost as quickly as I think of it, but with handwriting, I find myself thinking sentences ahead (even more than usual). My handwriting has therefore changed to accommodate my new speed and personality.
Before I exited this aside to return to my speech, I wrote:
Also, my wrist aches from all this writing.
Why was I writing by hand? Because I was in bed, and I had no computer that’s suitable for writing in bed. I had my iPod, but it’s too small for more than a few sentences at a time. A laptop would have worked fine in this situation, but I don’t have one.
Unsurprisingly, after surviving without handwriting for so long, I started to think. When would I ever write by hand?
- Situations where I don’t have a computer and I want/need to write, such as being in bed.
- I’ll have a laptop by the time I go to university which takes care of a lot of that.
- When I have to write:
- Writing a cheque
- Signing my name
- Filling in forms
- Leaving notes to people
- Writing my name on shit
- Writing a card
Can you see what handwriting has become, at least to me? It’s a novelty, something to do only when I have to – and even those times are decreasing. I can’t remember writing a cheque. I can text or email my family members instead of leaving notes. Forms can be filled out on a computer.
Why would I want to write by hand? It’s slow and painful, whilst on a computer you can easily write text that can then be copied around the world in seconds. Some people are fond of writing by hand, like how some people still buy CDs, but I don’t think there are going to be many such people for much longer.
This leads to the question: should we continue to teach children how to handwrite?
I think it’s obvious, or should be obvious, that eventually we’ll get to a point where writing by hand is never necessary, making the teaching of handwriting a waste of time. Handwriting is just a means to an end – that end being writing. There’s nothing inherently special about writing. Why continue to spend so long teaching kids to handwrite, when we could be teaching them how to type at 10,000 words per minute and other relevant skills ((For what it’s worth, I don’t think handwriting is lost if you can read. As long as you can recognise characters you should be able to reproduce them, though it may be time-consuming and the result scruffy. Handwriting can then be used if it is ever needed, or for a special effect (such as writing a love note).))? The debate therefore should be about when this happens, not if.
There is only one potential problem that I see: the sudden unavailability of electronic writing devices. After having thought about this subject, when I was on the train going to see my nephew, I wrote this question in my notebook ((Yes, I realise I’m writing by hand here: I don’t have a laptop yet.)):
“Is our reliance on technology a problem?”
Technology makes our lives much easier, but can we allow ourselves to make it even easier by completely depending on it; to forget our previous ways?
I think this is a really important thing to consider. I’ve had several discussions along these lines over the last few months, and I’ve read and thought about it too. Several ways in which we’re coming to depend on technology have come up:
- Typing rather than handwriting
- Students relying on search engines rather than memorising facts
- Having our books in electronic form rather than paper form
- Even just things like using a washing machine and a dishwasher rather than cleaning by hand
You know what? Although older generations might moan a little about the current generation having it easy, that’s the wonderful thing about technology. It makes our lives easier, so that we can focus on the things that are important. It’s writing that’s important, not handwriting. Being able to use facts, not being able to memorise them. Reading and not the paper. Having clean stuff, not cleaning. It all makes sense.
After much thought, I’ve concluded that once a technology is sufficiently reliable, we should embrace it and leave behind the more laborious, less efficient ways of doing things. If we’re always connected to the internet, why not rely on a search engine? If you’re always going to have electricity and a computer, why not stop teaching handwriting?
And now becomes clear the one downfall of relying on technology: the possibility of societal and technological collapse. Are we willing to accept this risk in order to enjoy a better life? The answer would seem to be yes: in the most important area that there is, the vast majority of us already depend completely on technology:
Survival
The world has a population of nearly 7 billion people. In the case of the collapse of society and technology ((see “The Road” and “Collapse”, which I will write about at some point)), without a doubt a lot of people just wouldn’t be able to survive. It’s only because of technology – fertilisers and pesticides and machinery – that the world has such a large population. It would be impossible. The vast majority have accepted reliance on technology just by living in this world.
That aside, even if the population were smaller, almost all of us have not learned the skills necessary for our survival in the wild. Read “The Road” by Cormac McCarthy if you want to get some idea of just how hard life would be after the collapse of society. I think I’d be pretty good at foraging, and I can make a decent shelter, but I can’t make clothes, I can’t hunt, and I don’t think I could defend myself very well.
Perhaps instinct would kick in, but I still think that most people would not survive for very long.
Should it be our duty to learn survival?
In my opinion, societal and technological collapse is it unlikely enough to happen that I am very happy to forgo survival knowledge for the benefit of an easier life. And, if I’m willing to accept that most important of reliances, surely it’s just a small step to allow my children growing up only knowing how to type. Come the end of our technological society, it doesn’t matter if we’ve forgotten how to wash our clothes and memorise facts and write by hand and wash our clothes – because we’ll be dead!
My philosophy has become: once a technology which can improve our lives has become sufficiently reliable, embrace it.
