I’ve been reading Ben Goldacre’s “Bad Science”. “Shocking” is one word I’d use. The people behind “Brain Gym”, “detoxing” footbaths, Patrick Holford, Homeopaths, most of the pharmaceutical industry, Gillian McKeith and others ought to be thoroughly ashamed of themselves.
“Puzzled” is another word I’d use. Why are so many trials, even those published in “prestigious” journals, misleading? Ben’s answer partly lies around:
1. Crap protocols
2. Crap write-up
3. Publication bias
I would like to make a suggestion as to how these three can be easily, and cheaply, combated. My suggestion is the, modestly titled, “Lloyd meta-protocol”.
The “Lloyd meta-protocol” is to be followed by a journal and consists of three things:
1. The publish/not publish decision is not taken after the results are known. Where it is to be published is not taken after the results are known. The decision is taken by peer-review of the protocol for the test. These protocols are published in the journal with space for letters criticising protocols. An amended protocol may be published making changes to meet criticisms of the protocol. No actual testing happens until after the protocol is “finalised”. (A protocol is “finalised” when a decision not to further amend it is taken.) Following this protocol actually stops badly designed trials being carried out.
2. The finalisation of the test protocol involves the advance acceptance of the paper by the journal and the agreement on the part of the researchers that there will be a paper. Any trials where the paper fails to materialise after a certain time-limit a reported on by a short one-paragraph assuming that the results were entirely negative. This part of the protocol protects against “publication bias”.
3. That agreement that the paper will be published might lead one to expect that any old crap knocked up by the researchers, with all the ways of being dishonest in the write up Ben told us about, will be accepted. The “Lloyd meta-protocol” avoids that by removing the task of writing up the paper from the research group and giving it to the journal. The test is written up by the journal. Sure, the research group will sit with the writer. The research group will suggest wording (perhaps, even, giving a draft of a paper to the journal) but the person who actually chooses which words are used and in which order will be a journal appointee.
Those “playing with a straight bat” should welcome these procedures. The criticism of the test protocols, at present, happens when all that expensive field research has been done. If those reading the paper are not happy about the protocols then that field research has been a waste of time and money. Under the Lloyd meta-protocol rejection happens early and rejection happens cheaply. They will be guaranteed the journal in which the results will appear. No need to sweat on this one, no need to work on some research only to find you can’t publish it in “Prestigious Journal” but only “Obscure Piece of Toilet Paper”. But there’s more. If “Prestigious Journal” follows the “Lloyd meta-protocol” then readers of the journal will know that all trials reported:
o Have peer-reviewed protocols
o Are not subject to publication bias
o Are written up independently of the researchers
In short, “Prestigious Journal” will become “Super-prestigious journal” and which researchers wouldn’t want to publish in that?
Those currently “playing it a bit dodgy” should be tempted by these procedures. As above, publication (if they followed the protocol) would be in “Super-prestigious Journal” following the Lloyd meta-protocol. How’s that going to sound? Pretty bloody good. If you’ve got a good product then you could make it look really good by playing a few dodgy tricks. But now you’d loose out on that “stamp of approval”. Does the prestige that can be got by fiddling protocols, dodgy write ups and publication bias really make up for the loss of the “stamp of approval”? Maybe, maybe not. But at least now they’ll have to think about it.
Medical professionals should adore these procedures. No more trailing through paper after paper just to find you should ignore the results. As well as publication in a Lloyd meta-protocol compliant journal being a “stamp of approval”, publication in a non-compliant journal is a warning sign. These people before they did the test were determined to do something dodgy. Avoid them:
- Try X, Y, Z it reduces the A, B, C count in populations 1,2,3
- Was that in “Super-prestigious Journal”?
- No, it was in “Obscure Piece of Toilet Paper”
- Go away then
- Try X, Y, Z it reduces the A, B, C count in populations 1,2,3
- Was that in “Super-prestigious Journal”?
- Yes, it was.
- Interesting, tell me more
The rest of us should welcome these procedures. Despite having read Ben’s book I do not have the ability to read through a medical research paper and, sorry Ben, I don’t really want to. I don’t think I can rely on an abstract (Ben’s taught me that much), but I’d be quite happy to rely on it if there was a big blue “Lloyd meta-protocol compliant” tick next to it.
The journals should welcome these procedures. It will increase their prestige (from prestigious to “super-prestigious) and, importantly, it’s easy for one journal to do it on its own, right now. We do not need a central registry of trials; the journal announces that it is its own registry. We don’t need some great world-conference to “renegotiate” a “settlement” on “conduct and publication of research”. “Obscure Piece of Toilet Paper” can remain as it is, you can’t hide bad results there anymore, just because “Super-prestigious Journal” (on its own) already has an agreement to publish it.
That’s probably the biggest argument in favour of the Lloyd meta-protocol: it doesn’t cost anything and you could start on Monday.
Saturday, 22 May 2010
The, modestly titled, Lloyd meta-protocol
Friday, 7 May 2010
What should the Liberal Democrats do next
This is the text of my email to the Party President on what the Liberal Democrats should do next. (You can send your own, details here)
"I was a member of the Liberal Democrats in its foundation year and, before that, the Liberal Party. I am in this for the long haul and think you should be too.
Let the Conservatives govern as a minority unless they guarantee substantive constitutional and electoral reform.
Do not sell out the long term constitutional good of this country for a few scraps of temporary power. Do not compromise on constitutional reform because you are frightened of the current economic crisis. Our mountain of debt will not be increased by multi-member constituency single transferrable vote. An elected second chamber will not produce a “double dip”.
Even were retaining the current constitution to reduce the pain that is to come such retention would be a short term move with long term consequences. Such short term thinking is exemplified (on a very much larger scale) by the movement of countries in crisis to totalitarianism. Yet we know that the quality of life in a country is inextricably linked with the quality of its constitution. Constitutional decisions now effect the whole of public life for decades to come. Take the right constitutional decision."
Tuesday, 27 April 2010
In a hung parliament a Lib Dem vote is a Lib Dem vote.
It’s on Twitter:
“Labour claim voting #libdems =voting Tories who claim #Libdems = Labour. Clearly #labservatives think voters = stupid”
(Tweeted by @El_Cuervo)
There is one big reason why a vote for the Liberal Democrats is a vote for the Liberal Democrats:
A hung Parliament
On 6th May your constituency will elect a Member of Parliament. Under the First Past the Post system beloved of David Cameron and Gordon Brown your MP would normally take up his seat in a House with a clear overall majority. As a consequence your MP would spend the next four to five years being ignored.
Most of the governing party’s MP’s sit on the backbenches and do as they are told. They vote in accordance with the whips dictates. Those who gain ministerial positions do so because they have set aside their personal convictions and their constituents interests to do what the whips tell them. The whips instructions come from the cabinet. Opposition party MP’s are totally ignored.
Unless your constituency elects a cabinet minister (and, face it, they’re all in such safe constituencies that your vote won't make a blind bit of difference) your representative will have no input. You’ll hear of the odd “rebellion” every now and again, but you know nothing will come of it. Those few MP’s brave enough to defy the whip are never enough.
In a hung parliament that changes. There will still be whips, of course. There will still be a cabinet, there will still be “party discipline”. But in a hung parliament each an every rebellion has a chance of success. Any combination of the three main parties has a majority. Each party has enough factions that, on an issue of real importance, sufficient rebels can be found.
Now I don’t think we’ll hear of many rebellions. For why is the exciting part: the cabinet will have to consult. They’ll want to make their policy and administration rebellion-proof. This they can only do, in a hung Parliament, by modifying their policy and administration to take into account the opinions of the House as a whole. Opposition MPs may still get a look in, for every opposition MP that supports you on one issue you can afford to annoy one of your own so the government will consult them as well.
Oh, it’s not going to be a utopian vision of calm rationality and open debate. Your MP won't have anything like a veto. It’ll be shouting, back room deals and party pressure. For the most part nothing will change but the MPs will not be ignored completely they will have some input. Which means that each and every Liberal Democrat MP elected will, whatever the governing coalition, have some real input into government of this country. MPs deciding things? MPs controlling the executive? No wonder Cameron doesn’t like the prospect.
But the value of a Liberal Democrat vote goes further than just the electing an MP who will be able to act, well, as an MP. A deal will have to be struck to create a government. A negotiation will take place. Most power in the negotiations will arise from the numbers of MPs each party can bring to the table. Some moral advantage, though, will come from the numbers of votes secured. Coming first in the vote will give more moral advantage than second, second more than third. 34% will count for more than 33%, not enough of course, but it will count. However miniscule the effect it will be more than the effect when a majority government is return: absolute zero.
Each and every vote for a Liberal Democrat will give some, tiny advantage to the Liberal Democrats in negotiations. Even if you live in David Cameron’s constituency, or Gordon Brown’s and have no hope of electing a Liberal Democrat MP it will have some effect. In this election no vote for the Liberal Democrats is “wasted”.
All votes will count.
Vote Liberal Democrat.
Saturday, 24 April 2010
Four suggestions on "proof" in libel
There are lots of things that need addressing in libel reform. Should corporations be able to sue? How on earth can we reduce costs to an acceptable level? And, of course, what "proof" should be presented and by which side. Below are three suggestions I have, not for "reversing" the burden of proof but re-thinking proof-in-libel altogether.
Facts, opinion and burdens of proof
The defences open to a defendant in English law depend on whether the words complained of express an “opinion” or a “fact”. Broadly (very – see here for a better outline ) if the words complained of make a verifiable claim then the defendant had better damn well verify it. The burden of proof here is firmly with the defendant. The complainant is not, in any way, required to show that the claim is false. If the words complained of are the expression of an opinion then (absent malice) the defendant need only show that it is an honest opinion.
In libel reform discussions it is often put forward that the burden of proof should be reversed: that the claimant should be required to show any factual allegations made to be false. This seems nice and simple but is fraught with difficulties. The difficulties arise because the fact/opinion dichotomy is too, well, dichotomous.
There are facts about the world, things that if said would be true. Unfortunately not all, in fact very few, of those facts are either known or readily discoverable. Thus we have opinions about facts.
Some facts we do not have "opinions" on or, if we do, we all share the same opinion or, if we don't, we consider those who differ in opinion lacking in knowledge, mad or bad. "Jack Kennedy was assassinated in Texas" is a fact in this sense. We can call "this sense" a "Fact", in inverted commas and with a capital "F".
If there are one or more putative “Facts” on which the case depends I see no problem in asking the complainant to establish them. The reason they are “Facts” is that they already have been established and their demonstration to others who do not accept them is a simple and straightforward matter. In the case imagined we could simply pull out a history book. Failure to meet a reversed burden of proof on this type of "Fact" would not unjustly disadvantage claimants: it merely invalidates the judgement that the case involves “Facts”. Pure “Facts” cases should be “open and shut” cases where, if the claimant can show that no informed person could reasonably believe what had been said then the claimant can cut out all the argument and the court starts looking at compensation.
But the vast majority of cases will not be decided on the basis of "Facts". They will have at their heart a putative fact such as “Lee Harvey Oswald assassinated Jack Kennedy”. Yes, this is a factual statement: one of “Lee Harvey Oswald assassinated Jack Kennedy” and “Lee Harvey Oswald is innocent” is a fact. But it is not a "Fact", we can reasonably put forward either one and "opinion" becomes inextricably mixed with fact. On the current "Fact"/verify "opinion"/honest basis, together with an understanding that most interesting facts are also matters of opinion, almost all libel cases would revolve around "honest opinion".
That seems way too broad to me. Interpreted one way it allows anyone to shoot their mouth off merely on the basis that they "honestly believe" an allegation. Interpreted another way it pretty well stops us saying anything at all. There is a difference between saying:
1. X is a paedophile
2. X cheated on his expenses
3. X supports Liverpool Football Club
All three are defamatory and any one of us may honestly hold that opinion about any other person. I would contend that whilst I could happily throw about the accusation that X supported Liverpool Football Club when there was not a jot of eidence I should have reasonable evidence for claiming that he cheated on his expenses. If I were to, publicly, claim that X was a paedophile then I should have very strong evidence indeed. The “honesty” of my opinion doesn’t enter into our judgements as to whether the claim can be put forward. The level of evidence required does and appears to vary with just how defamatory the accusation is. An overarching principle, such as “honestly held” would risk overriding that. If newspaper A alleged that X was a paedophile, X would effectively be prevented from seeking redress if all the defendant needed to show was that he had a conversation in a pub and as a result believed X was a paedophile. On the other hand my rights to free expression would be unfairly curtailed if I were not allowed to say “Dr. Evan Harris supports Liverpool” without conclusive proof.
Suggestion 1: Anything other than facts that are readily established, to the extant that anyone with knowledge, sanity and goodwill, should be treated as "opinion"
Suggestion 2: At the initial hearing in any libel case the claimant should be offered the opportunity to show that the allegations made would be recognised as false by anyone with knowledge, sanity and goodwill. If he established that then the court would, in that hearing, assess how defamatory the allegations were and what recompense (if any) was appropriate.
Suggestion 3: At the initial hearing the court should look forward to the likely damages that would be awarded as a way of determining the extent of the defamation caused by any opinion. Based on this the court would decide the nature and extent of reasons the defendant should have had before making the allegation.
Harm done and what is the defamation
We can consider a real case for this bit, the BCA’s claim against Simon Singh which they have recently discontinued after an adverse ruling by the Court of Appeal. The BCA contended that they were libelled (ie defamed unjustly) by the following words:
“The British Chiropractic Association claims that their members can help treat children with colic, sleeping and feeding problems, frequent ear infections, asthma and prolonged crying, even though there is not a jot of evidence. This organisation is the respectable face of the chiropractic profession and yet it happily promotes bogus treatments.”
The BCA press release of 15th April 2010 states that the BCA still considers that it was defamed by Simon Singh in the article. Of course it was defamed and remains defamed. Given the lightest reading from the Court of Appeal decision the article claimed that the BCA promoted treatments for which there was no reliable evidence without regard to that lack of evidence. That is not a good way for a professional body to behave. Any decent person should downgrade their opinion of the BCA on the basis of this. The words had a defamatory meaning. What has not been established is whether the words unjustly defamed the BCA and the BCA seems to accept that they have no hope of establishing that they were unjust. On the basis of this allegation the BCA have dropped the case: we can term it the “accepted” allegation.
The BCA had hoped to show that an allegation had been made that they had promoted the treatments when they knew that there was no evidence reliable or otherwise. It can be argued (indeed it was accepted) that Simon did not have sufficient evidence to establish that the BCA knew the state of evidence of the treatments. Neither could Simon have established that there was no evidence reliable or otherwise for the treatments. If one accepts that evidence can be unreliable and still be evidence (I don't) then the BCA have lots of evidence even though it is shit evidence. We can call the allegation of "no evidence, reliable or otherwise" and the BCA's knowledge the "disputed" allegation.
The issue before the Court of Appeal was whether Simon had made the accepted allegation or the disputed one. And it seems a fairly reasonable issue to address. If Simon had made the accepted allegation he was in the clear. If he had made the disputed allegation, an allegation he did not have good grounds to make, he was in trouble.
But hold on, what if:
1. The accepted allegation is just as defamatory as the disputed one and
2. Simon first (clearly) made the accepted allegation and later made the disputed allegation.
As above the level of evidence required to back up an allegation depends on the defamatory effect of the allegation. In this scenario the, later, disputed allegation has no defamatory effect: the BCA's reputation would have already been trashed by the accepted allegation.
Simon would appear to be varyingly liable dependent on the order in which he made the allegations. But this is clearly unjust. The damage to the BCA’s reputation does not similarly vary dependent on the order in which the allegations are made: the link between the damage Simon does and his liability is broken.
Suggestion 4: The court should break allegations apart. The grounds for making the allegation that the defendant need show should be set on the basis of the marginal defamatory impact of the particular part considered.
(In the BCA case, the court might have been unlikely to consider the marginal defamation of the disputed allegation to be nil. However the court may well have decided that the marginal defamation was not very much and, thus, that Simon had to show very liitle reason to make the allegation.)
Tuesday, 6 April 2010
In Defence of Hume’s Guillotine
It may, of course, be a false memory but I remember one clear sign that the last Conservative government had “lost it”. Minister after minister would be interviewed on television and repeat the mantra that they needed to better explain their policies. They saw growing opposition not as a sign that they should re-think their policies but that their policies were sound and anyone would support them if they were just communicated correctly. The idea that they were simply wrong never seemed to occur to them.
Sam Harris gave an eighteen minute “TED” talk entitled “Science can answer moral questions” and ran into some pretty forthright opposition. Much of this opposition Harris seemed to lay at the difficulty in properly explaining himself in the time available:
“18 minutes is not a lot of time in which to present a detailed argument” (Harris, 2010)
Listening to the talk I saw little that extra detail would add. My opposition, and the opposition of others, was guaranteed by the title. We subscribe to Hume’s Guillotine, the old maxim that you cannot derive an ought statement from an is statement. Harris mentioned the Guillotine in the opening minutes of the speech
“it’s often thought that there is no description of the way the world is that can tell us how the world out to be”.
Absent some pretty clear and interesting arguments that Hume’s Guillotine was wrong (and there were none such in the talk) it is clear that any moral system based on deriving ought from is would be wrong. No amount of explanation, no more clarity, would add to that. Harris had not fallen foul of a time limit but of a basic logical error. I am a little jealous of the pithy way Sean Carroll put it:
“Attempts to derive ought from is are like attempts to reach an odd number by adding together even numbers. If someone claims that they’ve done it, you don’t have to check their math; you know that they’ve made a mistake. (Carroll, 2010)”
Harris is of the opinion that not only is Hume’s Guillotine “clearly wrong” (the talk) but that there is something wrong in holding to it:
“Many of my critics piously cite Hume’s is/ought distinction as though it were well known to be the last word on the subject of morality until the end of time. Indeed, Carroll appears to think that Hume’s lazy analysis of facts and values is so compelling that he elevates it to the status of mathematical truth”
To be fair to Harris many people adopt Hume’s Guillotine unargued for. It is time that we examined the Guillotine, which I shall do below. We will not find it to be a “mathematical truth”, but will see that it is a logical one.
The claim made by Hume’s Guillotine
“In every system of morality, which I have hitherto met with, I have always remark'd, that the author proceeds for some time in the ordinary ways of reasoning, and establishes the being of a God, or makes observations concerning human affairs; when all of a sudden I am surpriz'd to find, that instead of the usual copulations of propositions, is, and is not, I meet with no proposition that is not connected with an ought, or an ought not. This change is imperceptible; but is however, of the last consequence. For as this ought, or ought not, expresses some new relation or affirmation, 'tis necessary that it shou'd be observ'd and explain'd; and at the same time that a reason should be given; for what seems altogether inconceivable, how this new relation can be a deduction from others, which are entirely different from it.”
(Hume, 1739)
The key claim is that some reason should be given for the introduction of an ought statement, a reason that cannot be given by however long a chain of is statements. It is not the claim that there are no moral facts, it is the claim that if there are moral facts then these do not derive from non-moral facts. It is not the claim that part of a moral argument cannot be formed of non-moral facts, that is statements cannot help in our formulation of ought statements. It is the claim that if we conclude “ought…” then we must have “ought…” somewhere in our premises: that there is a reason for “ought” and that is another “ought”.
The form of arguments
(By “arguments” I do not mean some disagreement or row. For “argument” I adopt the Monty Python definition: “a connected series of statements to establish a definite proposition”)
All arguments can be represented in the following form:
1. Premises
2. Conclusion
Arguments are generally split into deductive and inductive arguments with deductive arguments thought to be conclusive, whilst inductive arguments non-conclusive.
A deductive argument is one where, if the premises are accepted, the conclusion cannot be denied without contradiction. The old example is:
1. (Premise) All men are mortal
2. (Premise) Socrates is a man
3. (Conclusion) Socrates is mortal
If one were to deny Socrates’ mortality then, to maintain consistency, one would either have to deny than Socrates was a man (and thus deny the second premise) or claim the existence of at least one non-mortal man (and thus deny the first premise).
Non-conclusive arguments are termed inductive. The premises are held to be indicative of the conclusion, lend some support to the conclusion, make the conclusion more likely or whatever but the conclusion can still be denied without contradiction. Whilst we may conclude that “all ravens are black” because all the many hitherto seen ravens have been black there is no contradiction in believing that purple ravens may exist somewhere, have existed or will come to exist.
How conclusive arguments work
In the Socrates example we begin with a generalisation: “all men are mortal”. This statement has consequences, lots of them. It means that Plato is mortal, Aristotle is mortal, Cratylus and Xenophanes are mortal. It means that anything of which we can say “is a man” is mortal.
The second premise, “Socrates is a man”, picks out just one of those consequences. We could have picked out any of the other consequences, that about Plato or Aristotle or any of the others. The key issue is that we would be picking out a consequence of “all men are mortal”, a consequence that (to be picked out) must already be there. Before we make the specific statement that Socrates is mortal we have already said it in general.
Kant calls this picking out of consequence that is already there “analytic”:
“(I)f I say: “All bodies are extended,” then this is an analytic judgement. For I do not need to go outside the concept that I combine with the word “body” in order to find that extension is connected with it” (Kant, 1998, p. 130)
The conclusion to a conclusive argument contains no more than is contained in the premises of the argument.
Conclusiveness
Now all arguments on which we rely are, in a certain way, conclusive. That “certain way” is that we conclude. As a consequence, in principle, a logically conclusive argument can be reconstructed for any accepted proposition.
It is important not to confuse “conclusive” with “shown to be true”. If we conclude incorrectly then we still conclude and there are still reasons why we conclude how we did. “Conclusive” should not even be confused with “rational” or “reasonable”. If we come to an entirely unreasonable conclusion we do so because, well, we are being entirely unreasonable. We still have reasons why we conclude as we do even if they are not thought to be particularly good reasons.
If, for example, I conclude that “the pixies are after me” you might think me insane. “Insane” would be a reason put forward to explain my, otherwise odd, conclusion. Only insane people think that pixies are “after them” when everything else is normal and, given a few ancillary facts, certain types of insanity will lead one to believe in malevolent pixies. Here is the argument:
1. Pixie-type insanity
2. Ancillary facts
3. (Conclusion) The pixies are after me
The “pixie-type insanity” I have imagined above has as part of its consequences a range of situations where the sufferer (me) would become convinced that pixies were after him. The ancillary facts pick out one of those situations: situations that, as with individual mortal men, are already there. We need not go “outside the concept” of “pixie-type insanity” to find the conclusion.
On non-insanity inspired arguments, Kant expands his “containing” concept:
“in synthetic judgements I must have in addition to the concept of the subject something else (X) on which the understanding depends…(i)n the case of empirical judgements of experience there is no difficulty here. For this X is the complete experience of the object that I think through some concept A.(Kant, 1998, p. 131)”
When saying something about the world (“synthetic judgements”) requires us to go “outside” the concepts we hold. The concepts we hold do not “contain” descriptions of the world. To remain conclusive the arguments we put forward must have something about the world (the “X”) added to our premises. It is the fact that, from Hume’s arguments against induction, this X is contains more than we can possibly derive from empirical data that motivates the entire Critique of Pure Reason: where do the extra premises come from?
Whether or not Kant is successful in overcoming “Hume’s problem” (of induction) or, indeed whether Hume’ arguments against induction are sound, we can see the problem behind the critique: what reasons do we have for concluding on the basis of seemingly inconclusive arguments. How do we make the arguments conclusive?
The same issue faces us with “all ravens are black”. The evidence we have is not conclusive, it is compatible with a number of different propositions. Yet we do conclude. Somewhere, buried in our heads, must be another principle which, together with the arguments we put forward, entails “all ravens are black”.
Back to Hume’s Guillotine
If:
1. All arguments are conclusive
2. The conclusion of a conclusive argument is “contained” in its premises
then
3. A conclusion that expresses a “should” has a premise that expresses a “should”
---Edit---12th April 2010
Dave Lull has sent me a number of links to another blogger's detailed examination of the is/ought distinction in Hume:
Reading Hume on Ought and Is
http://branemrys.blogspot.com/2005/11/reading-hume-on-ought-and-is.html
On Ought and Is, II
http://branemrys.blogspot.com/2009/10/on-ought-and-is-ii.html
Hume on Ought and Is, Part I: Background
http://branemrys.blogspot.com/2009/09/hume-on-ought-and-is-part-i-background.html
Hume on Ought and Is, Part II: The Argument
http://branemrys.blogspot.com/2009/09/hume-on-ought-and-is-part-ii-argument.html
Hume on Ought and Is, Part III:
Conclusions
http://branemrys.blogspot.com/2009/09/hume-on-ought-and-is-part-iii.html
Is-Ought Muddles
http://branemrys.blogspot.com/2010/01/is-ought-muddles.html
Blackford and Is/Ought
http://branemrys.blogspot.com/2010/04/blackford-and-isought.html
Works Cited
Carroll, S. (2010, 03 24). The Moral Equivalent of the Parallel Postulate. Retrieved 04 05, 2010, from Discover: http://blogs.discovermagazine.com/cosmicvariance/2010/03/24/the-moral-equivalent-of-the-parallel-postulate/
Harris, S. (2010, March 29). Moral confusion in the name of science. Retrieved April 5, 2010, from Project Reason: http://www.project-reason.org/newsfeed/item/moral_confusion_in_the_name_of_science3/
Hume, D. (1739). A Treatise of Human Nature. London: John Noon.
Kant, I. (. (1998). Critique of Pure Reason. Cambridge: Cambridge University Press.
Monday, 15 March 2010
Do I have evidence that Chiropractic is the cause of AIDS?
In an earlier post I argued that the unit of evaluation/quantification of evidence is “all”. Now I turn my attention to its classification as evidence.
In the appeal the BCA's lawyer, Ms. Rogers, said:
(I)f Dr Singh had said "There is no reliable evidence", that is again a very different matter. Of course he could have said "There is no evidence that I think is reliable", but let us go a step further: that there is no reliable evidence. Again, it is very doubtful whether we would be here at all, because it would then be apparent -- if it had said "There is no reliable evidence", "The evidence is not good enough", or "There is no sufficient evidence", or something of that kind -- that that would be the kind of proposition which manifestly signals to the reader that we are in the land of debate and we are in the land of opinion. But, contrary, if we are into the land of "There is nothing". That is what "not a jot" means. It is not a figure of speech: "There is nothing".From Jack of Kent's blog, Jack got it from Marten Walsh Cherer Ltd.
Ms. Rogers is here drawing a distinction between evaluating evidence and classifying something as evidence. Classifying evidence determines whether or not it is evidence, evaluating evidence grades it once its existence has been established. The distinction is usually cogent. I might give Liverpool FC, mash potato and lager an extremely poor evaluation. This would be a judgement on my part. They would still though have a classification. Liverpool FC are a football team, mashed potato is food and lager is a drink. This is a cold, hard, fact. So Ms. Rogers here puts forward the arguement that even if Simon Singh has given evidence for Chiropratic as an effective treatment for colic, asthma etc. a very low evaluation it is still evidence. Judge it as he may it is simply a fact that the evidence exists. In a way the bad evaluation ensures the classification: surely, it can’t be unreliable evidence unless it is evidence?
Well there is a way. What is a football team, what is food and what is drink? A football team is a team that plays football. Food is a substance that nourishes. Drink is something that can be drunk. You cannot have a football team that does not play football, food that does not nourish and drink that cannot be drunk. You can have a football team that rarely plays football, food that has little nourishment and drink that we call ”undrinkable”. You can’t have non-playing-football-teams, non-nourishing-food and actually-undrinkable drink. If evidence were "stuff that you rely on" then "reliable evidence" would be akin to "nourishing food". "Unreliable evidence" could not be classed as evidence.
Ms. Rogers position on “unreliable evidence” appears to be akin to “horrible food”. Being reliable is a lot like being tasty. Its very important to be reliable/tasty and the more tasty/reliable it is the better. But even if it fails to be reliable/tasty it still is evidence/food even if it may be quite appalling evidence/food.
The question is invited: if "evidence" is not "stuff that you rely on" then what is it? I think that anything other than reliability would either:
1. Establish that I had evidence for "Chiropractic is the cause of AIDS" (or could "knock it up" pretty quick) or
2. Remove the classification of "evidence" from most of what we do claim to be evidence.
This is because every facet of evidence that is universal across evidence, other than relaibility, I can get for "Chiropractic causes AIDS". Pick one and I can get it. Pick one I can't get and there are other things that are clearly evidence that do not have it.
Evidence is claimed to support. I can claim that a pint of beer is evidence that Chiropractic causes AIDS. Evidence is believed to support. I can't believe the beer is evidence, but I may be able to find someone suffering from a mental illness who could. Evidence is the fulfilment of a prediction of a theory. "Chiropractic is the cause of AIDS" predicts that AIDS would have arisen after Chiroractic. AIDS did arise after Chiropractic. Pathetic evidence but, if evidence is the fulfilment of a prediction it is evidence. (If you want to play about with the Raven Paradox you can generate as many fulfilled predictions as you like).
Now I won't get my theory published in Pub Med, I won't get my theory published in any respected journal: but every criminal now in prison was convicted on the basis of "evidence" that never saw journal publication. Of course all that evidence in court was at least reviewed. But it was evidence before it was reviewed, and I can surely get people to review my evidence (nb it doesn't have to be favourably reviewed, the BCA's evidence certainly wasn't.) And on it goes. Food is used to nourish you, and so that is what it is. Evidence is used to help conclude epistemological decisions, to rely on in deciding what to accept, and so that is what it is.
So there we have Ms. Rogers' problem. She wants to split the factual question of whether there exists evidence or not from the judgement of whether that evidence is any good but it is the judgement of the reliability of evidence that establishes (or otherwise) the fact of it being evidence.
As I argued earlier that judgement must be on the totality of the evidence. A reasonable judgement on that evidence is that it is totally unreliable. Anyone making that judgement is forced to assent to the factual assertion that it is not evidence.
(As a little aside consider further what is being said by Ms. Rogers on behalf of the BCA: “it is very doubtful whether we would be here at all”. It’s not clear where “here” is. If it’s “in the court of appeal” then I don’t think the statement can be right. The appeal was, in part, about “bogus” and “happily”. Clearing up “not a jot” would not have cleared up the “bogus” and “happily” questions. Does Ms. Rogers mean “in a case for libel” by “here”? If so then it’s an astonishing admission: that it would not have been libellous (or, at least, not worth suing) on the accusation that the BCA had knowingly promoted treatments with insufficient evidence, with evidence that was not good enough or, even, with absolutely no reliable evidence what-so-ever!)
Wednesday, 24 February 2010
What does “not a jot of evidence” mean?
The “not a jot” comment in the BCA v Simon Singh libel case has re-reared it’s head now that it’s beginning to look like “bogus” and “happily” weren’t so libellous after all. What on earth is a “jot” of evidence anyway?
The philosopher John Watkins held that some people treated evidence as some sort of “juice”. These people treat evidence as a substance which you go about collecting and, as soon as you have enough, you have proved your point. Substances are easy to measure or, at least, easy to compare. We may not have a measuring jug handy to say that a has a gallon of x whereas b has only a pint but it’s pretty clear who has more. Substances also persist. You may only have a cupful but it is a cupful and will remain a cupful. If you have some evidence you may add to it to get lots of evidence but you will never go back to having no evidence at all. Finally substances are additive. If you have one pint of x and you add another pint of x then you have two pints of x.
Such an attitude is mistaken. Take ravens, as an example. It will be readily agreed that we have huge amounts of evidence for:
1. All ravens are black
Whilst we have no evidence for:
2. All ravens are male
Think about just exactly what that evidence is and, if we think in “juice” terms, we are bound to take it that we have a very good deal of evidence that, in fact, every single raven is male. Part of our evidence for ravens being a uniformly black species is that we have collectively seen huge numbers of ravens that are black. Let’s mentally take that evidence-juice and place it in the huge vat needed to accommodate it. Naturally with that much evidence we would have a pretty hard time denying that all ravens are black.
But we have also seen huge numbers of ravens that are male. In fact approximately half of all the huge numbers of ravens seen have been male. Mentally take that evidence-juice and place it in the huge vat next to the ravens-are-black vat. The juice will reach a level half that of the other vat. We could argue about whether it was enough, whether it had reached the level of “iffy” or “proven” or “certain”. We could not argue that it was nothing: which, of course it is.
The thing missed in this analysis is that sightings of black ravens on their own is no evidence at all for concluding that all ravens are black. Sightings of black ravens and no sighting of ravens of any other colour is. We could preserve the juice/substance by considering sightings of ravens of any other colour as a sort of “anti-juice”. If you see a black raven then you get a whisky measure of evidence-juice. If you see a raven of another colour then you get a whisky measure of anti-evidence-juice. The more black ravens predominate over other colours the more net-evidence-juice we have. At a cost of giving up persistence we save the juice concept of evidence.
This would work for “all ravens are male”. Each male raven seen would contribute a measure of evidence-juice, each female raven seen a measure of anti-evidence-juice. As half the ravens seen would be female the sum total of evidence would be zero.
It wouldn’t work for “all swans are white”. The existence of black swans does not reduce the amount of positive evidence for “all swans are white” but (no matter how few of them there are) is fatal for the hypothesis. Negative evidence in other areas is not so powerful: the odd bad game played by Everton reduces the evidence for, but is not fatal to, “Everton are the greatest team on earth”. It seems that we have to give up the idea of a nice, neat, additive nature of evidence.
Bayesian analysis seeks to replace a nice, neat, but unworkable, additive concept of evidence with a calculus of belief. If I test positive for disease a (Bayesians like to talk about diseases) then my degree of belief in “I have disease a” should increase. How much depends on how likely I am to test positive if I have the disease, how likely I am to test positive if I don’t have the disease and just how likely I am to have the disease (ignoring any evidence). But here we’ve gone another stage on: we have given up quantifying evidence and are now quantifying belief.
Yet we do speak of an “amount” of evidence. The evidence for “all ravens are black” is “huge”, the evidence for “all ravens are male” is “not a jot”. This is simply loose, colloquial, talk. It is not the evidence that is quantifiable (or, at least, rankable) but belief. The total evidence we have informs belief and, taking the degree of belief caused, we use this quantity to label all the evidence. The totality of evidence for “all ravens are black” is such that no reasonable person would doubt that all ravens are black. We are really sure that all ravens are black and, thus, label the totality of evidence that got us there “huge”. No reasonable and informed person thinks all ravens are male. Our degree of belief in “all ravens are male” is zero and so we use this to quantify the totality of evidence for “all ravens are male”. This is “zero”, despite the fact that there is substantially more than a plethora of male ravens.
So when someone says, for example, that there is “not a jot” of evidence for chiropractic as a remedy for asthma it does not mean that no trial has ever seen anything even vaguely compatible with chiropractic. What is meant is that, given the evidence, a reasonable and informed person would have “not a jot” of belief that chiropractic is a remedy for asthma.
