Wednesday, December 19, 2012

There is no coherent distinction between 'Principled' and 'Practical' arguments.

Allegedly 'practical' arguments assert that we should enact the policy in question because it will have some consequence.  For instance, one 'practical' argument in favour of using extraordinary rendition holds that it will increase public safety by enabling us to catch more terrorists.  But that means nothing unless we accept a prior principle that the consequence in question is desirable, i.e. that we should enact it.

Calling such an argument 'practical' is mostly a way of shirking the burden of defending such a principle.  It is a rhetorical sleight of hand - a way of saying, "Look, this principle is just so obvious that I shouldn't have to explain it, or weigh it up against the principles that the other side has advanced."

The hidden principle could be weak or strong.  If it is weak, e.g. "Other things being equal, we should do that which enables us to catch more terrorists.", then it's not clear that the premises of the argument entail its conclusion.  The whole point of the other side's case is that other things are not equal; for instance, that extraordinary rendition is brutal, inhumane, and damages the autonomy of ordinary innocent people.  If the hidden principle is strong, e.g. "We should always so act as to maximise the number of terrorists captured.", then it's not clear that the principle is so obvious as to require no defence.

Tuesday, November 13, 2012

Motion Fairness Analysis for Huber Debates 2012

Alfred Snider and James Hardy have been extremely kind (and unprecedentedly open) in sending me full tab data for a very recent tournament.  The Huber Debates 2012 involved 80 teams in 20 rooms, so it's just large enough that we get valid statistical inference using large-sample approximations.  I use the fairness test I describe here, which tests the null hypothesis that every team had an expected team score of 1.5.

Thursday, November 1, 2012

What does a good judge believe?

Recently, I said to a friend that I would find it deeply unpersuasive if a team made a case using the argument that homosexuality was immoral.  She was surprised by this, and told me that many debaters from her institution quite liked being judged by me, because they thought that I would give credit to any argument, no matter how weird it was.

It is probably true that I am more receptive to novel arguments than the average debate judge.  In fact, I often have to resist the temptation to reward an argument simply because it is novel and interesting.  But I'd like to think that I'm not indifferent between (for instance) a well-explained, internally consistent argument based on liberal principles, and an equally well-explained, consistent argument based on fascist principles.  So what gives?

Roughly speaking, good judges should act as intelligent, open-minded, neutral observers to an argument, willing to be persuaded by either side.  If judges hold extreme or unusual views, or hold usual views with unusual intensity, they should try as hard as possible to leave those convictions at the door and listen to arguments with a more moderate mindset.  They should be willing to have this internal monologue:  "Much as I think that this argument is not persuasive, that is in part because my views on this matter are unusually intense (or unusually well-examined).  Most reasonable people would be persuaded by this argument, and I shouldn't let the bad luck of encountering me as a judge disadvantage the team that made it."

However, that's not to say that judges should be tabula rasa, judging arguments based purely on their formal properties, devoid of moral intuitions, or assessments of whether a claim is persuasive.  It may be that some debating formats operate like this; and it may be that some debaters enjoy being judged like this.  (It takes all sorts to make a world.)  But that's not how BP debating works - and not how it should work.

Here are a few reasons why:  Firstly, almost no meaningful normative claims are purely logical.  (Non-philosophers often overestimate what is logically provable; that is, what can be shown to follow from logical axioms.)  If we are going to make meaningful normative claims in debates (e.g., "We should invade Iran if it is on the verge of acquiring nuclear weapons" or "We should provide for the sick, even when their illnesses result from their life choices) then we are going to need to start from more than pure logic.  If all starting points are treated equally, then debaters will always be talking past one another.  Debating will simply be a game of identifying an internally consistent ethical position that justifies your beliefs - no matter how morally repugnant that position is.

Thursday, June 28, 2012

A better fairness test

The fairness test that in my previous post had two problems:

  1. It was not sensitive to results other than first place.
  2. It could reject the null hypothesis that the motion is "fair" simply when one team's results had a lower variance.  Since it's at least folk wisdom that Opening Government teams typically have lower variance in their results, it could reject motions as unfair for reasons that are endemic to the format, and nothing to do with that particular motion.
After a bit of thought, I instead propose the following alternative:
A motion is fair iff the expected number of team points for a team in any position is 1.5.

This has the useful quality that it is sensitive to all the ranks that a team could attain, not just first place.  It also avoids mis-identifying variance issues as unfairness issues.  It seems, to me at least, that a particular position having a higher variance in its results does not ipso facto make a motion unfair.  It also seems to me a feasible standard, in that CA teams could reach it (with lots of effort, critical thinking, and a little luck).  (It is certainly more feasible than the extreme alternative, that teams in any given position must have an equal chance of coming first, second, third or fourth.)

What follows is a cookbook, so that any interested party could implement this test.  I assume a very basic knowledge of matrix algebra.  If you're not interested in the maths, feel free to skip to the end.

Wednesday, June 27, 2012

How to test whether a motion was fair.

I surely don't need to explain why a rigorous test of this form is useful.  I'm going to provide a cookbook to carry out such a test, and then a series of important caveats.  If you don't have time to read and understand the caveats, please don't apply the cookbook.  I realise many readers may not be interested in the maths, but if even a few tab geeks apply this, it may go some way towards having a rigorous and transparent way to discuss motion fairness after a competition.  This is a fairly easy test to construct and apply, but no one else seems to have done it, so I thought I'd make it available.


What follows is a likelihood-ratio test for the null hypothesis that a given debate motion was fair.  Here I take a particular (and contestable) definition of fairness: Namely, that teams in any given position have an equal chance of coming first.

Suppose there are N rooms, numbered i = 1,...,N.  Label the four positions (OG, OO, CG, CO) j=1,2,3,4.

Let bi,j be equal to 1 if the team in room i, in position j, came first, and equal to 0 otherwise. bj be the sample average of bi,j.  That is, let bj = ∑i bi,j/N .  Consider the statistic z, defined thus:

Under the null hypothesis that teams in a given position have an equal chance of coming first, z has an asymptotic Chi-squared distribution with 3 degrees of freedom.

Tuesday, May 22, 2012

What does it mean to say "This motion is fair"?

I didn't intend to start writing this post; my original line of thought was that it should be possible to devise a rigorous statistical test of motion fairness.  But it quickly became clear that, even though almost all debaters describe motions as "fair" or "unfair" in ordinary speech, and even though there are some agreed conventions for the use of these words, it is not at all clear that we know what we mean.

I'll present a series of intuitive definitions, and exhibit the problems with each:
(1) A motion is fair if teams in every position have an equal chance of winning.
Of course, this may not hold between teams of wildly differing skill levels, so we'd better modify this  to:
(2) A motion is fair if teams of equal skill level in every position have an equal chance of winning.
Using definition (2), or indeed, anything like it, suggests a problem that should be familiar to everyone who has set motions for a debating competition.  Motions can only be fair or unfair relative to the set of debaters expected to be debating them.  Anecdotal evidence suggests that many conceptually advanced motions (e.g. THBT the state should pay reparations to women.) may give all teams an equal shot at winning when all the teams in question are excellent debaters.  However, those same motions may be much harder for one side when debated between novices.  In some cases, this is because of a conceptual bar that teams must leap before being able to engage in the debate proper.  In other cases, it's because a certain level of rhetorical faculty is simply necessary to make some kinds of arguments convincing.  In any case, this is a problem not just with definition (2), but with any definition of fairness that is tied to outcomes between teams of equal skill.

Monday, February 20, 2012

Would that we had more of this.

The final of the LSE Open 2012 is an excellent example of what it means to debate outside the standard liberal paradigm.  All of the speeches are very, very good, and aspiring BP debaters would do well to observe the range of argumentative strategies and rhetorical methods deployed.

Infoslide: For the purposes of this debate, "Marxism" refers to a political ideology that:
1. Asserts that political activity is driven by class conflict
2. Argues that the free market is inherently exploitative
3. Advocates the abolition of capitalism and its replacement with an egalitarian economic system

The motion: This House Regrets the Decline of Marxism in Western Liberal Democracies.

The debate

Spoilers after the break.  (Really, watch it first if you don't yet know the result.)

Sunday, February 12, 2012

Prehistory recalled

On the motion: THBT democracy is a necessary condition for economic growth and stability.

Prop:  "How do we know that China is growing, if none of its growth is going to the people?!"
Opp:  "Its GDP is going up."

A New Standard for Knifing

Despite the best efforts of CA teams worldwide, there isn't really yet an operational standard for when it's acceptable for closing teams in BP to knife.  There are many different rules of thumb that judges follow, and these are seldom articulated explicitly.  This creates obvious problems that I will not belabour.  Teams should sometimes knife, and we need a clear rule for knifing that is common knowledge and is part of an overlapping consensus.

At Euros we proposed the following standard for knifing, which is an articulation of a rule of thumb that many (but not all) good judges use:  Teams should only contradict the team before them on claims that are plainly impossible to make persuasive to a reasonable person with common sense and a conscience.  These include gross factual errors and morally repugnant ethical positions.

Upon further consideration, I think that rule is problematic.  (I say that, as the person responsible for writing the briefing document that publicly advocated it.)  There are several problems with it:
  1. The rule involves a tricky judgement as to what the bounds of possibility in debating are.  Is it possible, for instance, to make extreme consequentialist positions persuasive to the hypothetical reasonable person?  Will she ever buy that we may eat babies that good may come?  Maybe there is a way to make the position persuasive, but the judge hasn't thought of it yet.
  2. The rule specifies a standard for behaviour but not the penalty for breaking it.  All good judges are agreed that knifing cannot be grounds for an automatic fourth (I do hope we can agree to this on a priori logical grounds, since obviously more than one team can knife).  One can contradict claims of varying degrees of centrality to the opening team's case.
  3. The rule commits teams to defending driftwood in the opening team's case.  If the opening team has made a weak claim that has been thoroughly rebutted, it may often be a more persuasive argumentative strategy to concede that claim, and instead argue a point that contradicts it.  ("Ok, so we concede that America bombing Syria will have a non-negligible effect on its government infrastructure.  In fact, there is a risk that it will in fact break the government into warring factions and plunge the country into anarchy.")
Because of that (and at the risk of adding to the existing muddle of rules of thumb) I'd like to propose a new standard for when it is acceptable to knife.  Namely: Closing teams that contradict a claim made by the opening team should be treated as though they had conceded entirely the opening team's claim.  The degree to which they are penalised should depend precisely on how that changes the overall persuasiveness of that teams case.

To take some illustrative examples, this means that a closing team that contradicts a weak or unpersuasive claim from the opening team, in order to replace it with a stronger argument, should be counted as thereby having made a net contribution to their side's case.  (Though, obviously, not as much a contribution as would be counted if adding this argument would have involved no knifing at all.)  By contrast, a closing team that contradicts a strong argument, central to the opening team's case, in order to replace it with a weak argument, should receive a penalty for having done damage to their side's case.

This straightforwardly addresses all three problems that I illustrated above.  (It is much easier for judges to decide which of two contradictory arguments is more persuasive, and how much so, than to decide when teams cross the line into "impossible" claims that trigger the possibility of knifing.)  I think it's a better standard, that means that the Opening teams arguments do affect and constrain what the Closing team can say, but only to the extent that those arguments are useful and persuasive.  It may, however, introduce new problems.  I'd be interested to hear what experienced judges think about it.

Sunday, February 5, 2012

How to get better at debating

Natural talent is, of course, a necessary condition for being an excellent debater.  But frequently the real bottleneck is getting serious about becoming a better debater.  This seems counter-intuitive; many moderately experienced debaters drive themselves to frustration, going to one competition after another without feeling any appreciable improvement.  They seem to exert great effort for little reward.

However, even though these debaters are trying hard at debating, they often aren't trying hard to improve.  Learning the initial steps of debating is easy; how the format works, how to structure a speech, the basics of speaking in public.  These are easy to teach.  Progress in these aspects is frequently swift and smooth.  But once that honeymoon phase is over, you need to take charge of your own development as a debater.  Improvement becomes much more difficult; it requires much more reflection and the ability to be self-critical.  Frequently one can plateau for a period of weeks or months, and any advancement comes in sudden, discontinuous jumps that accompany cracking the next step in an internal puzzle.

I'd like to give some advice to moderately experienced debaters who would like to try to become really good.  I'm not (in this post) going to give general recommendations about how to debate well; those will vary massively from case to case, and can be acquired from a rich variety of good sources.  To be precise, rather than advice, I'd like to give meta-advice; a set of directions for how to take charge of your own improvement.

Wednesday, February 1, 2012

Why Social Contract arguments are almost always wrong.

Social contract arguments are incredibly painful to watch.  A debater is making a speech.  He wants to argue that some person has such-and-such a legal right.  Or maybe such-and-such an obligation.  But he can't for the life of him think of why.  Flash of brilliance:  There exists a mythical contract that no one has ever seen or signed, and its terms include exactly the moral stipulation that he's looking to prove.

This approach has its slightly more contorted variations.  Maybe the social contract was broken, so the person breaking that contract is going to lose certain legal/moral rights.  (Often only loosely connected to the clause 'broken' in the first place.)  Or maybe the speaker asserts that the social contract involved some 'trading' of rights, where some pre-civilised caveman gained certain social duties in return for a right not to be clubbed over the head.  All these variations are also terrible.

Few top-tier debaters, and virtually no professional political philosophers, would nowadays make or defend the social contract argument as it is used in debating today.  Here's why:  Social contract arguments are transparently false and intellectually dishonest, even though they are so commonplace in debating that most debaters don't question their basic premises.  Let's run through several interpretations of what a 'social contract' could mean, and see why they are all deeply problematic.

Monday, January 30, 2012

Why I like motions about aliens and robots.

Many motions about aliens and robots are really debates about meta-ethics in disguise.  Without using any jargon or requiring formal training in philosophy, they make us consider genuinely novel entities, and ask ourselves what moral obligations we might owe to them (or they to us).  They are ideal debates to test moral reasoning from first principles, and the ostensible absurdity of their premises makes many of the cliché arguments seem out of place.  No one will argue that we owe obligations to aliens under some mythical social contract.

I'd like to set debates about Chapter 3 of Kant's Grundlegung zur Metaphysik der Sitten, but that would be a bit unfair.  So until such a time as we can run the Philosophy IV, I'll have to content myself with aliens and robots.

Sunday, January 29, 2012

An apologia for knowledge in debating

There is some controversy over the right level of assumed knowledge when setting motions.  I don't think very knowledge-heavy motions are particularly good debates, but I also think that motions should occasionally address specific issues, with proper nouns.  I'd like to defend a middle-ground standard as to the correct level of knowledge CA teams should assume of their teams, and then warn of certain potholes CA teams should avoid when setting knowledge-specific motions.

I think reasonable people can agree that it's no fun to lose debates due to ignorance of obscure facts.  It's frustrating to lose simply because the other side has an encyclopedic knowledge of the issue at hand, rather than because the other side is better at making and rebutting arguments.

At the same time, there are lots of fascinating issues in the world that involve specific people, policies and places.  It would be a shame never to debate about these.  Moreover, these are frequently more interesting when debated in specificity; that is, with reference to the particular people and places involved.  Compare the motion; "THBT Germany should ban the publication of Mein Kampf indefinitely." to the motion  "THBT Western Liberal Democracies should ban historically important racist texts."

Abstracting specific motions to a high level of generality has several harms:

  1. The motion loses its sense of immediacy; it frequently becomes harder, not easier for new debaters to see what the debate is about.  
  2. It becomes harder to put together good rhetoric when your statements have to encompass a messy gaggle of cases with many caveats and exceptions.  It is easier to condemn, applaud, regret, or be morally outraged in the specific rather than in general.
  3. Very general motions create the problem that in mid-level rooms debaters will trade examples rather than clash directly.  When a motion is abstracted to a high level of generality, there will typically be a few instances that serve prop and a few that serve opp.  Teams will frequently try to make sure that the instances that favour them get more airtime, which leads to a lack of clash in the debate.
  4. A related, but distinct problem:  Frequently the right answer to a very general motion is, "It depends."  Should we conduct airstrikes against repressive dictatorships?  It depends on the dictatorship, and the political situation in it.  Should universal primary education be a government priority in developing countries?  It depends.  In Malaysia?  Obviously.  In Somalia?  Obviously not.  Such motions risk having very arbitrary victory conditions; since most teams cannot prevail with their side in full generality, the question comes down to which side has covered 'most' of the cases in the world.  This is an empirical question that is very difficult to settle conclusively in a debate, and deciding which way it has been settled actually demands a very high level of knowledge from the judges.  
For the above four reasons, generalised debates about the same 'issues' are frequently poor substitutes for specific debates that demand some degree of knowledge from the teams.  Debates about general principles are frequently valuable and interesting; debates about specific situations are also valuable and interesting.  Neither is a perfect substitute for the other, and we should aim to have both kinds set as debates.

Thursday, January 26, 2012

watch this space

It's a bit of a busy week, but I've some ideas bouncing round that I'd like to write down.  When I get some space in my schedule, expect to see:

  1. An apologia for knowledge in debating.
  2. A statistical testing method for determining whether motions are fair.

Monday, January 23, 2012

Advice for new CAs setting motions

As it stands, knowledge about how to debate well is pretty effectively passed on from one generation of debaters to the next.  There are typically training regimens and/or coaching arrangements that pass on institutional knowledge, and good debaters will debate publicly often enough for many to learn by imitation.

However, there is one important bit of knowledge that has (so far) stubbornly refused transfer from generation to generation; namely, how to set good motions at a debating tournament.  Most of the process behind setting good motions happens out of the public eye, and even though the quality of the end result is plain to see, frequently the mistakes CA teams make are subtle and difficult to diagnose.

Setting good motions is difficult.  But I've been at this rather a long time, and I thought I'd make a list of recommendations.  Hopefully this will eventually lead to some kind of overlapping consensus on what constitutes best-practice for a CA team.

  1. Start thinking of motions months in advance.  Don't try to come up with motions on the day itself. When you set a motion at a reasonably sized IV, you are deciding what more than a hundred people will think and talk about for the next hour of their lives.  Take the time to do it right; if you've come up with a motion half an hour beforehand, it's unlikely that you'll have thought through enough of its implications to know how well it will turn out when eight intelligent debaters argue about it for an hour.  There are two reasons you should do this.  First, setting balanced motions requires thorough motions testing, which frequently cannot be accomplished on the day of the IV.  Second, setting interesting or inspired motions is a contemplative process.  Inspiration may strike five times over the course of a month, if you're being reflective and alert to world events.  Inspiration will almost never strike five times in the course of a day; so don't show up needing to create interesting motions on the fly.
  2. Be self-critical about your own ideas.  Have lots of ideas for motions, and winnow down ruthlessly.  Whatever you do, don't 'own' a motion and treat it as your child.  Frequently, ideas that seem cool or interesting at first sight may not turn out to be good debates, and you need to be able to acknowledge that in order to set motions well.  Most of the motions you initially think of will turn out to be problematic.  I typically generate dozens of motions for each IV , in the knowledge that less than a quarter of the motions I create will eventually make it through the testing process.
  3. Test motions thoroughly for balance and depth.  Ideally, you should get pairs of debaters (of varying skill levels) to prep each side of the motion, to make sure that they 'get' it.  But at a minimum, you should conduct the following tests:
    1. Ask yourself whether a debater who reads (but doesn't remember every detail from) reputable mainstream news sources would know what the debate is about.
    2. Check that there are at least five logically distinct, individually persuasive arguments on each side of the motion that are accessible to non-specialists. (Sometimes five isn't enough; this is a necessary but not sufficient condition for a motion to have depth.)
    3. Check that neither side has a silver bullet, that is, a persuasive argument that is so strong as to admit no effective answers.
    4. Ask yourself if experienced debaters whose only concern was victory would split roughly 50-50 on whether they would rather be prop or opp.
    5. For early rounds in the tournament, check that there are few ways for Opening teams to doom Closing teams by their incompetence.
    6. Ask yourself if it is possible for opening teams to 'break' the debate via sneaky definitions or policies.  (Put yourself in the mindset of an opening team looking to win the debate by whatever means necessary, however unsporting they are.)

Sunday, January 22, 2012

A Konami Code for APDA Debating

Suppose you're a BP debater about to debate on the APDA circuit.  Still, you're bewildered by all the jargon, and those Americans do speak awfully fast and seem to be judged on a metric you don't quite understand.  Two facts conspire to help you:

  1. APDA allows Government teams to list "caveats"; viz. propositions accepted as true by both sides for the purposes of the debate.
  2. APDA allows debaters to make meta-debate appeals to the judges.  (viz., that a round should be judged according to such-and-such a metric, for the following reasons.)
Therefore, when speaking in first prop, can one not caveat that victory should be determined according to the standards of BP debating?  Or, more appropriately, that victory should go to whoever is more persuasive, regardless of who "wins the flow" or answers every argument?

Also, after complaining about the misuse of the word "logical" in the worlds briefing, I encountered this weekend, for the first time in my life, a debate case that could be rebutted purely mathematically.  The policy constrained debt to follow one path, and net government spending to follow another path.  The problem:  Net government spending is the first derivative of the debt, so it was mathematically impossible for both paths to be followed at once.  By contradiction, QED.  Opp, of course, did not make this objection.

a statement of purpose

Straightforwardly: I'm an old dinosaur of debating, and after many conversational rants about motions and meta-debate issues, someone pointed out to me that this may be of interest to a wider audience.

This is not going to be your standard debating blog.  There will be almost no news about ongoing tournaments, and no hand-wringing about which-teams-will-break-on-what-points-this-weekend.  It will, hopefully, be an accumulation of interesting observations, thought experiments, and personal opinions about debating.  In many cases, I'll be wrong.  Someone once said something about the vivification of truth through its collision with error.