Tuesday, 16 December 2008
The other document, when I finally dug it out, was a print out of this page. So far as I can tell the main idea of the page is the idea that homeopathy is a little bit giving people vaccinations, which I guess is true, for sufficiently small values of "bit" - homeopaths give people a really really tiny amount of something that causes a disease and this makes them better. It then seems to claim that Pasteur therefore stole the idea of vaccinations from homeopaths.
Now, I'm not in a position to judge the historical accuracy of the document (although I can't help but find it somewhat suspicious - that's probably because I'm biased). But again, that's beside the point. The real question is, how is this in any way relevant to the applications of homeopathy in modern medicine?
If I'd gone up to a lecturer in my calculus II course asking for help on solving partial differential equations and they'd given me a link to some website which explained that Liebniz stole his theory of the calculus from Newton*, I would not have been much impressed - and I'm not even sure that analogy is quite ridiculous enough to explain how useless this document is to a medical student who wants to know more about how homeopathy works in practice.
Day 5 was today - I'll have an update sometime before the end of the week.
* NB - I'm not knowledgeable enough to have an opinion about that debate either, but at least it's an actual historical controversy.
Thursday, 11 December 2008
All I really know is that by the end of day 3 the students *still* hadn't seen any patients and that, when confronted with this fact the person in charge is reported to have said that this was because she was scared of what the students might say to the patients... Apart from this being a massive insult to the professionalism of the students, it is at least an encouraging sign that they have not been very effectively indoctrinated.
Day 4 consisted almost entirely of a 1/2 hour meeting with a patient (finally!) - details of which it would probably be inappropriate to publish - suffice it to say that it was rather a sad story.
Anyway, as I was saying, my decision to actually post this stuff (which I've been meaning to get round to for weeks) was prompted by an email I received this morning from a rather more prominent (and consistent) blogger than me, David Colquhoun (I hope I spelled that right), who has now picked up on the story. His email asked about how things have been going at the GNH, so I'm going to pass on the documents (when I find them) to him, and let him take the story from here.
Day 5 is this Tuesday, if there's anything interesting, I'll try to post sometime before Christmas...
First, as pointed out in the last post, the girlfriend told the "teacher" exactly what she thought of homeopathy (it's nonsense, it doesn't outperform placebo in proper blinded studies, etc.). She was challenged to bring in some evidence for her views (oops!) I was all for just taking Ben Goldacre's book, but the girlfriend thought taking something with "Bad Science" on the cover might be a bit too antagonistic, so we looked up some references and she took some metaanalyses instead. Needless to say, these were ignored.
She was then given some documents to take home and peruse as "evidence" that homeopathy works. The first of these genuinely astounded me. It was a document entitled (I kid you not) "An Overview of positive homeopathy research and surveys". (online here)
This document is published by the "European Network of Homeopathy Researchers". A network which has practically zero presence on the web apart from having authored this document, and which is sponsored by the European Council for Classical Homeopathy, but let's forget about it's provenance for a second... an overview of positive research?
I'm sure anyone who is reading this doesn't need me to point out quite how ridiculous this idea is, but my girlfriend hadn't realised until I did, so I'm going to make it explicit here. Imagine I have a dice and I roll it 10,000 times, calling every set of 10 rolls a "trial". I then decide to publish only those "trials" which say that my dice is biased towards the number 6. There are going to be an awful lot of "trials" which give statistical support to this hypothesis (at the 95% level, approximately 50 of them) - does this mean my dice is biased?
It reminds me of the overcomplicated slogan I wanted to get put on a t-shirt once "Is homeopathy better than a placebo? 1 in 20 trials say YES with 95% confidence", and unfortunately confirms my hypothesis that homeopaths just wouldn't get it.
There are many, many more flaws in the document (several trials are repeated, most of them are flawed, the wrong figures are quoted from several) but it's hardly worth taking it to pieces when it's such a ridiculous thing to write in the first place.
There was also some other document about homeopaths having more sympathy for Jenner than the medical establishment at the time, or something like that... I didn't actually read it and I can't seem to find it - but I'll dig it out.
Not much else happened - still no patient contact. Yes, that's right, the "Medicine in Society" module where the students get to see how medicine is practised by real-life practitioners and by day two, still no actual medicine being practised.
Saturday, 25 October 2008
The homeopath asked "does anyone know anything about homeopathy", and my girlfriend told her. She apparently went into quite a lot of detail about Avogadro's constant, the fact that every drop of water on the planet should already be a homeopathic remedy for everything and the fact that homeopathy just doesn't work. (To be fair, of course, as Ben Goldacre would say "it's a lot more complicate than that", but the pills don't work any better than any other sugar pills). The homeopath stood there, listened, thanked my girlfriend (I might need to come up with a codename if I'm going to keep doing this... or get her to let me use her real name) for her contribution and then went on to explain about what the various tablet do.
She told them all she'd give them some free arnica tablets next time (for general aches and pains, I believe) and offered to give a few of them medicine for various conditions if they hadn't cleared up in two weeks time, and then finished with an exhortation to "do some research about homeopathy". Her suggested source was the Society of Homeopaths website which I'm sure would offer a "Fair and Balanced" view. I'm going to give her a copy of Ben Goldacre's book,as well as a few of the better meta-analyses.
As for the (very helpful) point made in the comments about using the experience to learn about why people feel the need to go to these people for help instead of using medicine that actually works - yes, we've already talked about that - it is a good chance to see something that she probably won't get to see working in hospitals or on future ward rounds (although asking the patients tactfully why they aren't seeing a traditional doctor might be a challenge). Still, that's not the way the hospital treats it - they consider it an opportunity to watch real-life health professionals at work in the field. Also, I apologise about the comments I made about the qualifications of the psychotherapists at the Centre - I was not happy at the time, and it was unnecessary.
Anyway - the visit didn't go too badly, everyone was polite and, whilst I don't think she got much out of it, my girlfriend was slightly more happy than she expected to be - at least she got a chance to air her views. We'll see how things go next week when she'll have more contact with patients.
Tuesday, 21 October 2008
Among other things, they offer "Holistic Aromatherapy", "Homeopathy", "Cranial Osteopathy", "Cranio-sacral therapy" (on reading the blurb on the website, I honestly can't see any difference between these particular two brands of woo) , and the Reiki Healing. Even when some of the treatments sound as though they might be sensible (Pyschotherapy, Relationship Counselling...) it turns out that some of the practitioners are the same people who do the Reiki healing. Although, to be fair, some of them do seem to be qualified psyhotherapists (not, note, qualified pychiatrists).
There doesn't appear to be a single person on the staff at GNH who is a qualified medical doctor (I haven't looked through the entire list, I'm willing to be corrected on this) and one woman proudly offers her qualifications as "BA Hons", "DipTch", which unless I'm mistaken is just a Bachelor's degree (in an unspecified (arts) subject) and a teaching diploma.
Anyway, that's enough trashing the place - obviously, it's a hotbed for woo, and they don't really buy into the whole "evidence-based medicine" thing. Fair enough, there's a time and a place for that sort of thing, as Ben Goldacre points out in his new book, there are probably more important things to worry about, but this is where the story gets silly.
On hearing that she was going to be sent to woo-central, and not really liking the idea, my girlfriend decided to ring up the School and ask if she could possibly be transferred to a placement where they did actual medicine. She was told in no uncertain terms that she could not, and that if she didn't attend all eleven days of woo-school, she couldn't possibly pass her second year. An extract from this conversation apparently went:
My Girlfriend: "But there's absolutely no evidence that any of it works, it's not based in science."
Office Lady: "That's a fair point, but..."
"but..."? But what? What "but..." could possibly justify forcing someone to waste 11 days and (approximately) £1000 of tuition fees on learning about treatments that can't possibly work? Possibly the scariest part about this is that the other twenty or so medical students who were sent on the same placement don't seem to have objected at all.
Anyway, today is day one of her placement. She's promised to take copious notes, and I'm going to write about them here.
Sunday, 1 June 2008
Yes, it would be a tragedy if an asteroid hit the Earth and killed us all, or if we managed to kill several billion people in a nuclear war, but is there really any moral imperative to privilege future intelligent beings which happen to be made out of the same sort of squishy stuff as we are ahead of future beings that are made out of silicon, or toilet paper and stones, or whatever it might be? When I read Eliezer's story about the Alien Message, I'm on the side of the people - and not just because they're made out of the same stuff as me. Put the people outside the box, and I'd be on the side of the computers. Is trying to develop friendly AI really a rational goal? Or is it an obvious bias?
Disclaimer: I haven't read Eliezer's wiki post of the Knowability of Friendly AI yet - some of the questions I ask here might well be answered there.
Wednesday, 28 May 2008
The paradox as presented by Cohen is horribly worded, and doesn't even manage to reach the status of contradiction, but that's not really anything new. In it's standard "barber" form, it goes:
Imagine a town with only one male barber, the Elders of the town are seriously committed to everyone having neat hair, so they require *by law* that the barber cuts the hair of everyone, and only those people, who does not cut their own hair. No-one else in the town is allowed to do any hair cutting. Everyone's hair must be cut.
So, does the barber cut his own hair? Obviously he can't, because then he wouldn't be allowed to cut it by law, but he must, because no-one else can cut it either. Blah, blah. The conclusion, one would think, is that this is a really silly law. Bertrand Russel certainly thought so (and never endorsed the "paradox" in this form).
However, it is supposed to be a version of Russel's real paradox - "The set of all sets which do not contain themselves". This set, it seems can neither contain itself or not contain itself, as either would lead to a contradiction. However, to simply declare that, like the barber, this set doesn't exist is rather rash - it undermines the axiomatic set theory that Russel spent a lot of his life developing. Luckily, it doesn't undermine Zermelo-Fraenkel Set Theory, so mathematics didn't entirely collapse in on itself.
Tuesday, 15 April 2008
modulo primes numbers. I've already done Independent Set, and when I finally get round to finishing the corrections on my paper, that's hopefully going to go up on ArXiv (I guess that X is supposed to be a chi, but I can't be bothered to figure out how to generate special characters, so I'm not going to).
So far, we know that counting graph homomorphisms exactly is hard (except when it's trivial), that counting colourings mod p is also hard (except when it's trivial), and that counting independent sets is hard. Conjecture: if H has trivial automorphism group, then counting the H-colouring problem is hard modulo p for all p. Actually, I guess that doesn't qualify as a conjecture yet - it's more of a speculation. So far the only evidence we have in favour is that we can't see why it wouldn't be true.
So, I'm off to read Dyer and Greenhill (paper is probably gated if you're not in an academic institution, and probably completely incomprehensible if you don't study computational complexity at at least postgraduate level). And hope that some of their proof techniques can be extended to my world.
Monday, 14 April 2008
Protagoras was a lawyer, and a teacher. He was a teacher so confident in his own abilities that he used to agree very unorthodox remuneration packages with his students - with one, Euathlus, he agreed that he would receive *no* payment unless the student won his first case. Having completed his training, Euathlus decided that he didn't want the shame of losing a case, but he also didn't want the cost of paying Protagoras: his solution? Don't take on any cases.
Protagoras' was not happy with this turn of events, and decided to sue for his tuition fee. His argument was simple. If Eualthus won, he had won his first case, and must pay Protagoras. If he lost, then he had to pay Protagoras by order of the court. Either way, Protagoras must be paid.
Eualthus, however, had obviously been listening in his lessons. He argued that if he won, he did not have to pay Protagoras, by order of the court. However, if he lost, he clearly would not have to pay by virtue of their agreement.
To me this has never seemed either very interesting or very paradoxical - Eualthus should win, as he hasn't yet won a case. Then Protagoras can sue him *afterwards* for the tuition fee (as Eualthus will now have won his first case). However, if we are to take the paradox at face value, it is simply another liar paradox, which we will meet again, and discuss at greater length at that juncture.
Friday, 11 January 2008
But unfortunately they don't seem to have made it for very good reasons. It has long been a mystery why concert promoters don't charge enough for their concert tickets (they fill the stadiums and have people queueing round the block at the prices they do charge, they could certainly fill them at some higher price). It is just as much of a mystery why anyone would object to "ticket touts" taking advantage of this.
If people are willing to pay 3500 euros for a ticket to go and see Liverpool get convingly trounced by AC Milan, then why shouldn't they be allowed to pay it? The tout wants the money more than the ticket, and the fan wants the money more than the ticket. It's win-win. Ticket touts are providing a valuable service. So why the vitriol? I think it's mostly because they don't teach economics in schools (seriously, I'd never heard of the Invisible Hand before I was about 18 - most people I know probably still haven't, it's all well and good getting worked up about not teaching evolution, but which is actually more relevant in day-to-day life?).
The government committee apparently conceded that ticket touts to provide some benefits to consumers, apparently noting that "where venues are not full, touts sometimes sell tickets below face value.", whilst failing to note the equally valuable service they provide by getting the tickets to the people who are most willing to pay for them when venues are full.
Not a single one of the articles I've read has mentioned the very simple fact that if the concert organisers really did "resent" seeing their tickets change hands without them getting any recompense, they could soon solve the problem by the very simple mechanism of raising the price of the tickets. Like I said, it's always been a mystery why concert promoters don't charge enough for their tickets. Maybe the internet-inspired boom in the touting industry will give us some evidence that might help explain it.
Thursday, 10 January 2008
This is the second problem in the book, and it is also available online here (same place as the last one). It's about knowledge, and I'm not sure how interesting it is - I think it's probably a real philosophical problem as opposed to one of those which doesn't even make sense to think about. It's about the nature of knowledge:
THE COW IN THE FlELD*Well, I think the answer is obviously no. He wasn't, was he? Imagine the dairyman had found out that Daisy wasn't in the field, then it couldn't possibly be true that he "knew" she was there when she wasn't? Could it?
Farmer Field is concerned about his prize cow, Daisy. In fact, he is so concerned that when his dairyman tells him that Daisy is in the field, happily grazing, he says he needs to know for certain. He doesn't want~ just to have a 99 per cent idea that Daisy is safe, he wants to be able to say that he knows Daisy is okay.
Farmer Field goes out to the field and standing by the gate sees in the distance, behind some trees, a white and black shape that he recognises as his favourite cow. He goes back to the dairy and tells his friend that he knows Daisy is in the field.
At this point, does Farmer Field really know it?
The dairyman says he will check too, and goes to the field. There he finds Daisy, having a nap in a hollow, behind a bush, well out of sight of the gate. He also spots a large piece of black and white paper that has got caught in a tree.
Daisy is in the field, as Farmer Field thought.
But was he right to say that he knew she was?
One issue which Cohen fails to address in his discussion of this problem which I think is actually interesting is whether or not it is possible to know something that isn't true. Cardinal Ratzinger "knows" that Christopher Hitchens is going to Hell (I was going to say he knows I'm going to Hell, but I doubt he knows who I am, I guess he's heard of Hitchens). Hitchens "knows" that he isn't. Clearly one of them is wrong, but both would be very confident in their knowledge. Nor is this phenomenon restricted to untestable propositions like the existence of Hell - homeopaths "know" that their medicine works. I "know" that it doesn't. We both know that I'm right - but in what way does this affect our definition of knowledge?
Cohen proposes that knowledge be defined as that which is true, believed, and believed for a good reason. He then asks us what we need to add to this definition to explain why we don't think that Farmer Field knows that Daisy is in the field. He doesn't come to any conclusions. Nor can I - which leads me to wonder whether this is an interesting question after all. When we both know what knowledge is - "we know it when we see it" - does it really matter if we have a concrete definition? And if we did have a concrete definition, would "knowledge" necessarily be the same thing as "connaissance" - I think the problem of translation is one of the main reasons I can never get too interested in debates about the meanings of words.
Thursday, 3 January 2008
Cohen's answer to this problem is (essentially) you should say "I will be boiled in oil". Clearly, they now can't boil you in oil or hang you by the neck until you die (they could, of course, just feed you to the native fauna without breaking the rules of their game - Cohen's scenario attempts to get round this, but doesn't quite succeed).
I heard the story of a sailor stranded on a lost island.
Unfortunately (for the sailor), that island was inhabited by some very bad guys.
The bad guys said to the sailor:
"You are to be executed. As we're slightly insane bad guys, we will allow you to say one phrase.
If you speak a false sentence, you will be boiled in oil;
If you speak a true sentence, you will be hanged by the neck your until you die."
Well - that's just boring. Firstly, there's an infinite list of statements which have the same self-negating truth properties as "I will be boiled in oil". Starting from the obvious "the statement is not true", and ranging to some more intriguing ones:
- "Quand precedé par sa traduction en francais entre guillemets n'est pas vrai" when preceeded by its translation into French in quotation marks is not true.
- This sentence claims to be an epimenides paradox but it is lying.
- If the meanings of "true" and "false" were switched then this sentence wouldn't be false.
There is much more to Judge Dredd's tale than Cohen gives it credit for. The same, in my opinion, will be true of several of the other stories when we come to them.
Anyway, so far as I'm aware none of the problems he addresses are original (although all of the little fables that introduce them probably are) so I'm going to go through the book and post my thoughts on the problems as I go along. I'm mostly doing this because I find some of Cohen's answers very unsatisfying - not just in the sense that they don't answer the questions, but in the sense that they don't even seem to notice why the question is interesting.
I'm not entirely sure it's legal for me to do this. I'm fairly sure it should be though. I'll discuss that in more detail if and when I come to problem 32... The next post will be Problem 1.