I've just seen the ISS for the first time. We realised it was due to go over, so popped outside. Lovely clear evening. Bright light in the sky. Is that it? Or is it that one below it? It's the one below: it's moving! Wait, there's another one next to it, also moving! That can't be right. No, it's the bright one that's moving!
It was a very peculiar optical illusion, making the bright light seem to be still in the sky, and the fainter one seem to be moving. After the few seconds of confusion, we watched the bright light move overhead. It whipped overhead quite fast, covering half the sky in a few minutes. It was very bright, probably about magnitude -3. As it got closer to the horizon, it dimmed and brightened a few times, then disappeared.
Observing astronomical stuff is cool. But watching the ISS was quite a different feeling -- people did that! A whole other level of cool.
Monday, 25 April 2011
Thursday, 21 April 2011
legal science fiction
Labels:
science fiction
I occasionally get emails about my website, including questions about SF. I'm no expert, but sometimes I (or more often, my other half), can provide a bit of an answer.
Here's the latest question in my inbox:
I don't know of any bibliography, but I (rather, we!) can provide a few more examples, after a quick trawl through memories and bookshelves. One trope is to use a trial to get the protagonist out of the military, or out of society, so they can go off adventuring, or go undercover, or something; see, for example, E. Everett Evans, Man of Many Minds. We've tried to avoid listing such "trivial" trials that are there just to set the (otherwise unrelated) plot going, and to list ones where the trial is an integral part of the story (if not always the focus). But there is no sharp line.
Lloyd Biggle Jr, Monument, is about establishing and gathering evidence for court cases about who owns a planet, and uses an obscure point of tax law to win the day.
Miriam Allen deFord's anthology Space, Time and Crime has several relevant stories. Check out "The Adventure of the Snitch in Time"'s throwaway reference to a famous lawyer.
Cory Doctorow, Little Brother, has a trial.
There are court cases in Heinlein novels, such as whether Lummox is a pet in The Star Beast, and whether humanity should be allowed to survive, in Have Space Suit, Will Travel.
Frank Herbert's Bureau of Sabotage stories can involve court cases: see "The Tactful Saboteur" and The Dosadi Experiment.
In Larry Niven, "The Ethics of Madness", the court case is central to the plot.
Niven and Pournelle's Oath of Fealty includes a murder trial, where the defence is essentially that it's okay to kill someone who is shouting "fire" in a crowded theatre. It's not central to the plot so much as indicative of the overall philosophy of the book.
Pohl and Kornbluth, Gladiator-At-Law, might fit the brief.
Jerry Pournelle's "High Justice" features a Solicitor General.
Charles Sheffield, Space Suits, is a collection of short stories about Burmeister and Carver, Shysters-at-Law, and their legal exploits in the solar system. He has also written the short story "Humanity Test", which is at the opposite end of the humour spectrum.
Robert Sawyer, Illegal Alien, has an alien visitor tried for murder.
Cordwainer Smith, "The Crime and the Glory of Commander Suzdal", ends in a trial -- well, a verdict -- about the use of a time machine to create an entire sentient race.
There is a whole sub-genre about whether something non-human (computer, robot, alien, uplifted animal) should be given the status of human. Probably Asimov's "The Bicentennial Man" is top here, with also Heinlein's "Jerry was a Man". Scalzi's The Android's Dream includes a scene about the legal status of one of the protagonists.
MilSF is replete with courts martial. For example, there is the court martial of Pavel Young in David Weber's Field of Dishonor, and a couple of courts martial in Heinlein's Starship Troopers (one being used as an example to the hero not to request his own court martial later!).
There are alternative legal systems -- for example, ones where the whole community gets to vote on a punishment, such as in Alexei Panshin's Rite of Passage.
If we are allowed TV SF, there are some Star Trek episodes revolving around court cases, and there is the Battlestar Galactica trial of Gaius Baltar.
Any more?
Here's the latest question in my inbox:
I'm writing short stories about law. The story criteria are:
1. Uninvented technology. This is, to me, the sine qua non of SF.
2. The story focuses on law. A simple reference to a statute is insufficient.
Police procedurals are unacceptable.
Examples of good stories of this sort: "A Loint of Paw," by Asimov; "The Sixth Palace," by Silverberg.
Is there a bibliography already done, the subject of which is SF law stories as I define that category?
Have you any recommendations for the bibliography? I'm a bit short on novels which fit the criteria. Only the Circuit trilogy by Snodgrass comes to mind.
I don't know of any bibliography, but I (rather, we!) can provide a few more examples, after a quick trawl through memories and bookshelves. One trope is to use a trial to get the protagonist out of the military, or out of society, so they can go off adventuring, or go undercover, or something; see, for example, E. Everett Evans, Man of Many Minds. We've tried to avoid listing such "trivial" trials that are there just to set the (otherwise unrelated) plot going, and to list ones where the trial is an integral part of the story (if not always the focus). But there is no sharp line.
Lloyd Biggle Jr, Monument, is about establishing and gathering evidence for court cases about who owns a planet, and uses an obscure point of tax law to win the day.
Miriam Allen deFord's anthology Space, Time and Crime has several relevant stories. Check out "The Adventure of the Snitch in Time"'s throwaway reference to a famous lawyer.
Cory Doctorow, Little Brother, has a trial.
There are court cases in Heinlein novels, such as whether Lummox is a pet in The Star Beast, and whether humanity should be allowed to survive, in Have Space Suit, Will Travel.
Frank Herbert's Bureau of Sabotage stories can involve court cases: see "The Tactful Saboteur" and The Dosadi Experiment.
In Larry Niven, "The Ethics of Madness", the court case is central to the plot.
Niven and Pournelle's Oath of Fealty includes a murder trial, where the defence is essentially that it's okay to kill someone who is shouting "fire" in a crowded theatre. It's not central to the plot so much as indicative of the overall philosophy of the book.
Pohl and Kornbluth, Gladiator-At-Law, might fit the brief.
Jerry Pournelle's "High Justice" features a Solicitor General.
Charles Sheffield, Space Suits, is a collection of short stories about Burmeister and Carver, Shysters-at-Law, and their legal exploits in the solar system. He has also written the short story "Humanity Test", which is at the opposite end of the humour spectrum.
Robert Sawyer, Illegal Alien, has an alien visitor tried for murder.
Cordwainer Smith, "The Crime and the Glory of Commander Suzdal", ends in a trial -- well, a verdict -- about the use of a time machine to create an entire sentient race.
There is a whole sub-genre about whether something non-human (computer, robot, alien, uplifted animal) should be given the status of human. Probably Asimov's "The Bicentennial Man" is top here, with also Heinlein's "Jerry was a Man". Scalzi's The Android's Dream includes a scene about the legal status of one of the protagonists.
MilSF is replete with courts martial. For example, there is the court martial of Pavel Young in David Weber's Field of Dishonor, and a couple of courts martial in Heinlein's Starship Troopers (one being used as an example to the hero not to request his own court martial later!).
There are alternative legal systems -- for example, ones where the whole community gets to vote on a punishment, such as in Alexei Panshin's Rite of Passage.
If we are allowed TV SF, there are some Star Trek episodes revolving around court cases, and there is the Battlestar Galactica trial of Gaius Baltar.
Any more?
Elisabeth Sladen, 1948-2011
Labels:
Doctor Who,
obituary,
science fiction
I was wondering what to say. Then I saw this on Dork Towers, which captures the mood precisely.
I grew up traumatised by Doctor Who (in the best possible way).
Well, I never really grew up, of course. I was a fan of the spin off Sarah Jane Adventures, too.
Goodbye. You are missed.
I grew up traumatised by Doctor Who (in the best possible way).
Well, I never really grew up, of course. I was a fan of the spin off Sarah Jane Adventures, too.
Goodbye. You are missed.
Wednesday, 20 April 2011
all hail anaesthesia
Labels:
medicine
I was having a tooth prepared to receive its cyborg implant (or crown, as a dentist would more mundanely call it). The conversation went like this:
I can barely imagine life without anaesthetic -- and frankly, I don't want to.
Curious observation: the two injections were painful, too, but a very different quality of pain from the drilling. I had no trouble sitting there as the needles went in, but that drill in my incompletely-numbed tooth -- no way.
"Would you like some anaesthetic?" asked my dentist.Then, a couple of hours later, when the numbness wears off, the tooth starts saying to me, "hey, I've just been drilled, you know?". So I take a paracetamol, and everything's groovy again.
"What are you going to do?"
"Drill."
"Yes!"
Large needle is carefully pushed into my upper gum.
Pause, waiting for it to take effect, then drilling proceeds.
"Eek!"
"A bit tender still? I'll put some more anaesthetic in, then."
Large needle is carefully pushed into the roof of my mouth.
Pause, waiting for it to take effect, then drilling recommences.
And continues, painlessly.
I can barely imagine life without anaesthetic -- and frankly, I don't want to.
Curious observation: the two injections were painful, too, but a very different quality of pain from the drilling. I had no trouble sitting there as the needles went in, but that drill in my incompletely-numbed tooth -- no way.
Tuesday, 19 April 2011
AV or not AV? That is the Referendum.
Labels:
politics
On the 5th of May, the UK has a referendum on whether to change the way we vote for our MPs from the current "first past the post" (FPTP, the "No" campaign) to the Alternative Vote system (AV, the "Yes" campaign).
I had been intending to vote "Yes" (for AV). Then I saw material from the "No" campaign. That material has swayed my decision –- to absolutely absolutely vote "Yes". The "No" campaign's distortions and/or stupidities are just shocking. (It is interesting to see the campaign, since there are party members from both major parties in each of the Yes and the No camps -– strange bedfellows indeed.)
So, what’s the fuss?
With FPTP, you have a list of N candidates, and put a cross next to one of them; the candidate with the most crosses wins. With the proposed AV, you have a list of N candidates, and rank them, putting 1 for your first choice, 2 for your second. You can go all the way up to N, ranking the lot, or stop sooner, when you don’t care about the ranking of the rest. The first preference (those with a 1) are counted. If someone gets more than half these votes, they win (this is only likely in a "two horse race", or where the further "horses" are rank outsiders). Otherwise, the candidate who came last (the one who fewest voters wanted as first choice) has their second preference votes redistributed to the rest. This carries on (the last candidate’s votes redistributed) until someone has more then 50%, and wins.
AV sounds more complicated than FPTP. Well, it is more complicated than FPTP. But that doesn't necessarily mean it's worse.
Consider the following scenario. There are three main parties, the PolkaDots, the Maroons, and the Turquoises. The PolkaDots are a minority party, but with quite a big following, about 20% of the vote. The Maroons and Turquoises are roughly evenly split: about 40% each. I support the PolkaDots, am tolerant of the Maroons, but really really hate the Turquoises.
Under FPTP, who am I going to vote for? The Maroons, of course. I can hear the campaign now: "a vote for the PolkaDots is a wasted vote"; "a vote for the PolkaDots is really a vote for Turquoise/Maroon" (depending on whether it’s a Maroon or Turquoise statement). So hardly anyone votes for the PolkaDots: 20% of the electorate are in some sense disenfranchised.
Under AV, however, I can safely put PolkaDots first, then Maroons. I probably leave off the Turquoises, or put them third, depending how I decide to indicate my disgust with them. (In fact there's always a smattering of really minority candidates: I hate the Turquoises so much I'll even put the looney StripyParty above them, but I'll put the Turquoises above the CrossHatches, who are just plain evil). My support for the PolkaDots gets counted, even though they come third, and then my second choice is given to the Maroons, who win. I'm not devastated: PolkaDots third again, but at least I got Maroons, who I can live with, and my real support for the PolkaDots got counted.
But maybe, just maybe, enough people do this, and hey, the Turquoises come third. Their votes are redistributed. And since no Turquoise supporter would be seen dead in Maroon, their second choice votes are for the PolkaDots. And we win! And those Turquoise voters aren't devastated either: they came third, but at least the hated Maroons didn't win. The compromise candidate dissatisfies least.
Sounds sensible enough. Maybe there is a hidden problem that makes AV disastrous? After all, there's Arrow's theorem, that basically says, given some axioms desirable in any voting system, the only voting system that obeys those axioms is a dictatorship. So it seems there is no "fair" voting system: maybe AV is less fair than FPTP?
If so, the FPTP "No" campaign will be pointing this out. So, let's look. Oh.
I caught the end of a TV broadcast for the "No" campaign, without knowing what it was. First of all, I thought it was comedy sketch, mocking the stupidity of people who couldn't understand AV. Then I thought it was a slightly tasteless "Yes" campaign broadcast, mocking the stupidity of people who couldn't understand AV. It was only at the end that I realised it was a "No" campaign broadcast (presumably self-mocking their own stupidity?)
Then their campaign leaflet fell through the letterbox.
One: it starts with the slogan "Keep One Person, One Vote". The slogan "One Person, One Vote" is part of the universal suffrage campaign, for people who don't have a vote at all. AV isn't going to remove people from the electoral roll. Fear mongering.
Two: complaints about the cost -– "£250 million", the cost of electronic vote counting machines and education in the new system. This is contrasted with what else the money could be spent on (always a dubious tactic -– just because money isn’t spent on one thing doesn’t mean it will be on something else): "2,503 doctors, 6,297 teachers, 8,107 nurses, 35,885 hip replacements or 69,832 school places". First of all, notice the tiny "or" in there: it's doctors OR teachers OR nurse OR hips OR school places, but formatted to look like them all. Also, is that a salary for a month, a year, the lifetime of the person? Compared to the £250M, is that per year, per election, or what? Bad statistics.
Three: "The second or third best can win under AV" versus "Under our present system, the one who comes first is always the winner". Notice that weasely use of the word "best". Voting for your Parliamentary representative is not at all analogous to a horse race or foot race, where the fastest, the best, is first past the winning post. It's more analogous to a group of people choosing where to go for an evening's entertainment, where 40% love skating, hate football, and are fine with the cinema, and another 40% love football, hate skating, and are fine with the cinema, and the final 20% love the cinema (and they all have to go to the same place, rather than split up). With AV, it's the cinema, and everyone is reasonably happy; with FPTP it's either football or skating, with 40% very unhappy. What then is the "best" choice? Why should the "one who comes first" (is most people's first preference, even though that's a minority of the people) be the winner? After all, under FPTP, just because there is a majority for someting doesn't mean there isn't a bigger majority against it! Undefined (and misleading) terminology, combined with false analogy. (I can’t complain that they use "FPTP" terminology, as this is the standard name for the system; I can complain when they use it as an analogy, poorly).
This is accompanied by a photograph of a foot race, with an arrow to the guy in last place (subtly dressed in black, to boot), saying "The winner under AV", not so subtly implying this it what always happens. (There's also the minor fact that the person who comes last -- has fewest first preference votes -- can never win under AV, as their votes get redistributed first.)
Four: "It is wrong that the person who came second or third can overtake the person with the most votes and be allowed to win because the second, third or even lower choices of supporters of extreme parties such as the BNP are counted again and again and again." More fear mongering, by naming an extremist minority party. What about other, non-extremist, minority parties? If I like the looney StripyParty, so put them first, then the PolkaDots, then the Maroons, then the Turquoise, why shouldn’t my wish for the Maroons-more-than-Turquoise be counted just as much as that of a Maroon-firster? (This argument appears to be the source of the "Keep One Person, One Vote" slogan.)
One argument the No campaigners don't use in their leaflet, but that I have heard others use, is that AV might even allow some nasty extremists to gain power (if they were everyone's second choice, say). Well, there's a name for specially designing an electoral system so that it stops those nasty people you don't like from winning: undemocratic. Rather than squelching all those nasty bigots by disenfranchising them, I'd much prefer a system that helps educate them out of their bigotry, and an electoral system that doesn't encourage extremism in the first place. So I was disappointed by the Electoral Reform Society's otherwise excellent site on AV, for saying that AV "penalises extremist parties, who are unlikely to gain many second-preference votes." I would rather it said that such parties wouldn't end up with an unfair advantage (thereby countering the fear-mongering) rather than "penalises" (which smacks of being undemocratic).
Anyhow, off to vote "Yes" on 5th May. Is the referendum itself FPTP, or AV? Well, it's a "two horse race", so it doesn't matter – the result is the same either way.
I had been intending to vote "Yes" (for AV). Then I saw material from the "No" campaign. That material has swayed my decision –- to absolutely absolutely vote "Yes". The "No" campaign's distortions and/or stupidities are just shocking. (It is interesting to see the campaign, since there are party members from both major parties in each of the Yes and the No camps -– strange bedfellows indeed.)
So, what’s the fuss?
With FPTP, you have a list of N candidates, and put a cross next to one of them; the candidate with the most crosses wins. With the proposed AV, you have a list of N candidates, and rank them, putting 1 for your first choice, 2 for your second. You can go all the way up to N, ranking the lot, or stop sooner, when you don’t care about the ranking of the rest. The first preference (those with a 1) are counted. If someone gets more than half these votes, they win (this is only likely in a "two horse race", or where the further "horses" are rank outsiders). Otherwise, the candidate who came last (the one who fewest voters wanted as first choice) has their second preference votes redistributed to the rest. This carries on (the last candidate’s votes redistributed) until someone has more then 50%, and wins.
AV sounds more complicated than FPTP. Well, it is more complicated than FPTP. But that doesn't necessarily mean it's worse.
Consider the following scenario. There are three main parties, the PolkaDots, the Maroons, and the Turquoises. The PolkaDots are a minority party, but with quite a big following, about 20% of the vote. The Maroons and Turquoises are roughly evenly split: about 40% each. I support the PolkaDots, am tolerant of the Maroons, but really really hate the Turquoises.
Under FPTP, who am I going to vote for? The Maroons, of course. I can hear the campaign now: "a vote for the PolkaDots is a wasted vote"; "a vote for the PolkaDots is really a vote for Turquoise/Maroon" (depending on whether it’s a Maroon or Turquoise statement). So hardly anyone votes for the PolkaDots: 20% of the electorate are in some sense disenfranchised.
Under AV, however, I can safely put PolkaDots first, then Maroons. I probably leave off the Turquoises, or put them third, depending how I decide to indicate my disgust with them. (In fact there's always a smattering of really minority candidates: I hate the Turquoises so much I'll even put the looney StripyParty above them, but I'll put the Turquoises above the CrossHatches, who are just plain evil). My support for the PolkaDots gets counted, even though they come third, and then my second choice is given to the Maroons, who win. I'm not devastated: PolkaDots third again, but at least I got Maroons, who I can live with, and my real support for the PolkaDots got counted.
But maybe, just maybe, enough people do this, and hey, the Turquoises come third. Their votes are redistributed. And since no Turquoise supporter would be seen dead in Maroon, their second choice votes are for the PolkaDots. And we win! And those Turquoise voters aren't devastated either: they came third, but at least the hated Maroons didn't win. The compromise candidate dissatisfies least.
Sounds sensible enough. Maybe there is a hidden problem that makes AV disastrous? After all, there's Arrow's theorem, that basically says, given some axioms desirable in any voting system, the only voting system that obeys those axioms is a dictatorship. So it seems there is no "fair" voting system: maybe AV is less fair than FPTP?
If so, the FPTP "No" campaign will be pointing this out. So, let's look. Oh.
I caught the end of a TV broadcast for the "No" campaign, without knowing what it was. First of all, I thought it was comedy sketch, mocking the stupidity of people who couldn't understand AV. Then I thought it was a slightly tasteless "Yes" campaign broadcast, mocking the stupidity of people who couldn't understand AV. It was only at the end that I realised it was a "No" campaign broadcast (presumably self-mocking their own stupidity?)
Then their campaign leaflet fell through the letterbox.
One: it starts with the slogan "Keep One Person, One Vote". The slogan "One Person, One Vote" is part of the universal suffrage campaign, for people who don't have a vote at all. AV isn't going to remove people from the electoral roll. Fear mongering.
Two: complaints about the cost -– "£250 million", the cost of electronic vote counting machines and education in the new system. This is contrasted with what else the money could be spent on (always a dubious tactic -– just because money isn’t spent on one thing doesn’t mean it will be on something else): "2,503 doctors, 6,297 teachers, 8,107 nurses, 35,885 hip replacements or 69,832 school places". First of all, notice the tiny "or" in there: it's doctors OR teachers OR nurse OR hips OR school places, but formatted to look like them all. Also, is that a salary for a month, a year, the lifetime of the person? Compared to the £250M, is that per year, per election, or what? Bad statistics.
Three: "The second or third best can win under AV" versus "Under our present system, the one who comes first is always the winner". Notice that weasely use of the word "best". Voting for your Parliamentary representative is not at all analogous to a horse race or foot race, where the fastest, the best, is first past the winning post. It's more analogous to a group of people choosing where to go for an evening's entertainment, where 40% love skating, hate football, and are fine with the cinema, and another 40% love football, hate skating, and are fine with the cinema, and the final 20% love the cinema (and they all have to go to the same place, rather than split up). With AV, it's the cinema, and everyone is reasonably happy; with FPTP it's either football or skating, with 40% very unhappy. What then is the "best" choice? Why should the "one who comes first" (is most people's first preference, even though that's a minority of the people) be the winner? After all, under FPTP, just because there is a majority for someting doesn't mean there isn't a bigger majority against it! Undefined (and misleading) terminology, combined with false analogy. (I can’t complain that they use "FPTP" terminology, as this is the standard name for the system; I can complain when they use it as an analogy, poorly).
This is accompanied by a photograph of a foot race, with an arrow to the guy in last place (subtly dressed in black, to boot), saying "The winner under AV", not so subtly implying this it what always happens. (There's also the minor fact that the person who comes last -- has fewest first preference votes -- can never win under AV, as their votes get redistributed first.)
Four: "It is wrong that the person who came second or third can overtake the person with the most votes and be allowed to win because the second, third or even lower choices of supporters of extreme parties such as the BNP are counted again and again and again." More fear mongering, by naming an extremist minority party. What about other, non-extremist, minority parties? If I like the looney StripyParty, so put them first, then the PolkaDots, then the Maroons, then the Turquoise, why shouldn’t my wish for the Maroons-more-than-Turquoise be counted just as much as that of a Maroon-firster? (This argument appears to be the source of the "Keep One Person, One Vote" slogan.)
One argument the No campaigners don't use in their leaflet, but that I have heard others use, is that AV might even allow some nasty extremists to gain power (if they were everyone's second choice, say). Well, there's a name for specially designing an electoral system so that it stops those nasty people you don't like from winning: undemocratic. Rather than squelching all those nasty bigots by disenfranchising them, I'd much prefer a system that helps educate them out of their bigotry, and an electoral system that doesn't encourage extremism in the first place. So I was disappointed by the Electoral Reform Society's otherwise excellent site on AV, for saying that AV "penalises extremist parties, who are unlikely to gain many second-preference votes." I would rather it said that such parties wouldn't end up with an unfair advantage (thereby countering the fear-mongering) rather than "penalises" (which smacks of being undemocratic).
Anyhow, off to vote "Yes" on 5th May. Is the referendum itself FPTP, or AV? Well, it's a "two horse race", so it doesn't matter – the result is the same either way.
Sunday, 17 April 2011
Total Eclipse of the Flowchart
Labels:
algorithm,
Bonnie Tyler,
Doctor Who,
science fiction,
web
I'm a Meatloaf/Bonnie Tyler/Jim-Steinman-as-lyricist fan. And the song "Total Eclipse of the Heart" has extra sfnal resonances for me, too. Several years ago, at a Science Fiction convention, I watched Dave Lalley's "Miscellaneous 2" tape, a compilation of 1970s and 1980s TV clips of adverts and songs. Near the end is a wonderful edit of a load of Dr Who (ToS) clips to Bonnie Tyler's TEotH -- marvellous. Nowadays there are several different YouTube videos, featuring clips of the new Doctors.
So when my other half said "Google Total Eclipse of the Heart flowchart", I did. And found the wonderful
at jeannr's blog. (Although the professional in me is obliged to point out that it isn't a flowchart, but a railroad track syntax diagram.)
Digging further through this marvellous blog, I found that the idea had been further elaborated by her followers. There's a more detailed chart
and even a video of the chart being drawn dynamically as the song is sung (by the cast of Glee, but, hey).
I love the Web.
So when my other half said "Google Total Eclipse of the Heart flowchart", I did. And found the wonderful
at jeannr's blog. (Although the professional in me is obliged to point out that it isn't a flowchart, but a railroad track syntax diagram.)
Digging further through this marvellous blog, I found that the idea had been further elaborated by her followers. There's a more detailed chart
and even a video of the chart being drawn dynamically as the song is sung (by the cast of Glee, but, hey).
I love the Web.
A History of Celtic
BBC4 (the new BBC2) is currently showing a four part series "A History of Celtic Britain", presented by Neil Oliver, he of the delicious Scottish accent, and of the permanent crick in his neck as he strides along addressing comments to the camera just behind his left shoulder. I love the awe and excitement with which he fondles prehistoric artefacts; I love somewhat less the Just So Story feel to the "wholesale returns of conjecture out of such a trifling investment of fact" that follows discovery of some fragment of bone juxtaposed with some fragment of rust. (We play the game of coming up with different "plausible" explanations of why someone was buried with three spears, or curled up with a mirror, or whatever.)
We record this series so that we can watch it at the weekend. Our PVR truncates the title to "A History of Celtic". This might not seem so odd, except that "Celtic" by itself refers to a football team, and is pronounced with a soft C ("Seltick"), whereas in "Celtic Britain" it is pronounced with a hard C ("Keltick"). Hmm.
We record this series so that we can watch it at the weekend. Our PVR truncates the title to "A History of Celtic". This might not seem so odd, except that "Celtic" by itself refers to a football team, and is pronounced with a soft C ("Seltick"), whereas in "Celtic Britain" it is pronounced with a hard C ("Keltick"). Hmm.
Tuesday, 12 April 2011
I can't go deeper
A few days ago, I came across this quotation:
Funnily enough, the examples given always stop around the depth shown above. That's because although we can recurse 4 or 5 or 6 deep, we can't (well, I know I can't) go much deeper. My stack overfloweth.
Unboundedness requires us to be able to recurse to a depth much much more than 6. It requires any depth: to a hundred, to a trillion, to a googolplex, and beyond. Clearly, it is nonsensical to think that we can do this.
I believe that some of the writers who come up with such statements about unbounded recursion think we need it to get a sufficiently large number of sentences. But even without it, there is no problem that we might run out of thoughts. Combinatorics is quite sufficient to give a ridiculously huge number of possible sentences. "The small purple octopus frowned thoughtfully as it slowly drank cold green tea from the heavy pewter mug held gently in its fifth tentacle" -- I bet that's never been said before! And the number of sentences that follow just this one particular, rather simple, structure is mind-bogglingly huge (even the number that actually make some kind of sense).
So let's dispense with the idea of "an infinite number of sentences thorough unbounded recursion", please. We don't need to go that deep.
We humans can take an entire proposition and give it a role in some larger proposition. Then we can take the larger proposition and embed it in a still-larger one, creating a hierarchical tree structure of propositions inside propositions. Not only did the baby eat the slug, but the father saw the baby eat the slug, and I wonder whether the father saw the baby eat the slug, and the father knows that I wonder whether he saw the baby eat the slug, and I can guess that the father knows that I wonder whether he saw the baby eat the slug, and so on. Just as ability to add 1 to a number bestows the ability to generate an infinite set of numbers, the ability to embed a proposition inside another proposition bestows the ability to think an infinite number of thoughts.I've seen many similar such examples, and they all say that because we can recurse, we can think (or generate) an infinite (I think they mean unbounded) number of thoughts (or sentences).
---Steven Pinker, How the Mind Works, pp124-5, Penguin, 1997
Funnily enough, the examples given always stop around the depth shown above. That's because although we can recurse 4 or 5 or 6 deep, we can't (well, I know I can't) go much deeper. My stack overfloweth.
Unboundedness requires us to be able to recurse to a depth much much more than 6. It requires any depth: to a hundred, to a trillion, to a googolplex, and beyond. Clearly, it is nonsensical to think that we can do this.
I believe that some of the writers who come up with such statements about unbounded recursion think we need it to get a sufficiently large number of sentences. But even without it, there is no problem that we might run out of thoughts. Combinatorics is quite sufficient to give a ridiculously huge number of possible sentences. "The small purple octopus frowned thoughtfully as it slowly drank cold green tea from the heavy pewter mug held gently in its fifth tentacle" -- I bet that's never been said before! And the number of sentences that follow just this one particular, rather simple, structure is mind-bogglingly huge (even the number that actually make some kind of sense).
So let's dispense with the idea of "an infinite number of sentences thorough unbounded recursion", please. We don't need to go that deep.
Monday, 11 April 2011
Snakes alive! -- and plastic
Labels:
3D printer,
garden
First frogs in our garden pond, now snakes. Here's a happy grass snake sunning itself in the bright April sunshine, stretched out along part of the spaceship in our pond.
But we also have a new plastic snake.
The Makerbot 3D printer arrived at work last week. Now assembled, it has printed a couple of test-snakes, a test-Millennium Falcon, and a test-project logo.
It has also destroyed two of its three plastic conveyor belts (tip: don't try to print at a z-coordinate less than zero).
The snake shown here (about 11cm, or 4.5", long) took about 20 minutes to print.
A colleague at work, seeing our newtoy tool, asked "why do you want a 3D printer"? Who wouldn't want one? I think he meant "what are you going to use it for?" Printing antennae for robots, actually. To start with.
There has been lots of hype about 3D printers, so I was not expecting the surprising feeling I got when I picked up the plastic snake. It's tougher than I expected (although I have now broken it, of course...), and yet it's flexible. And the resolution is better than I was expecting.
Forget jet packs. This is the 21st century.
But we also have a new plastic snake.
The Makerbot 3D printer arrived at work last week. Now assembled, it has printed a couple of test-snakes, a test-Millennium Falcon, and a test-project logo.
It has also destroyed two of its three plastic conveyor belts (tip: don't try to print at a z-coordinate less than zero).
The snake shown here (about 11cm, or 4.5", long) took about 20 minutes to print.
A colleague at work, seeing our new
There has been lots of hype about 3D printers, so I was not expecting the surprising feeling I got when I picked up the plastic snake. It's tougher than I expected (although I have now broken it, of course...), and yet it's flexible. And the resolution is better than I was expecting.
Forget jet packs. This is the 21st century.
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