How To Win Every Argument
Gervase Markham
LUGRadio Live 2007
Before We Begin...
- This is the first time I've given this talk
- Not comedy "as such"
Arguments
- Arguments on the web are very common
- Usenet
- Wikipedia editing
- Web forums
- Bugzilla
- Logical errors ("fallacies") can mislead, confuse and obfuscate
- This talk is that opportunity to learn how
- Appearing to prove your point is much easier than actually proving it
Logical Fallacies
- Fallacies can be named and classified
- Latin names make you sound authoritative
- We will look at several of the more common and useful, including examples
- Examples reflect my personal experience
Loaded words
- Using words which have perjorative meanings
- The "Literate Programming" fallacy
- A keen favourite of politicians and the media
- My change is "reform"; yours is "tinkering" or "meddling"
- We don't tend to spot these when used by our own side
"During last night's demonstration, the occupying Israeli military murdered five Palestinian activists.
During last night's violent riots, the Israeli peace-keepers shot dead five Hamas terrorists.
Slippery slope
- A single step in a particular direction must inevitably take you all the way
- The "Conservative" fallacy
- Use to: oppose any sort of change
- Very common in arguments in the Mozilla project about implementing IE-only features
"And this will continue until such time as browsers take a stand. Should we also
implement all the bugs that Internet Explorer and Netscape 4.x have in their
CSS parser? Hell no!" -- Ian Hickson, discussing implementing support for the Symbol font
Dicto simpliciter
- An argument made upon a sweeping generalization
- The "Eat Your Greens" fallacy
- Use to: counter an argument without bothering to do any research
"Biblical scholars say the Gospels were written long after the events they record and are distorted by the viewpoint of the author and the need for the accounts to address the situation of the early church."
Argumentum ad temperantiam
- If there are two possible options, a middle way must be the best solution
- The "British" fallacy
- The foundation stones of New Labour and the Church of England
- Used in: the "how long can we detain terror suspects without trial?" debate
"The Third Way is the route to renewal and success for modern progressive politics. Neither old left nor new right, it takes the essential values of the centre and centre-left... and applies them to a world of fundamental social and economic change, free from outdated ideology." --
Tony Blair
Definitional Retreat
- Changing the meaning of words when someone raises an objection against the original wording
- The "No True Scotsman" fallacy
-
Audio: The five best things about Britain, 00:24 - 00:46
- Tip: claim a plausible meaning, such as technical vocabulary
"Of course, I was using "expectation" as statisticians do, multiplying the probability of
the returns by their size. I didn't mean it in the sense that we expected anything to happen..."
False Analogy
- Equating two things which are not, in fact, the same
- The "Pastafarian" fallacy
- If the analogy is not spotted, you can prove almost anything
"The Bible is just a bunch of myths and fairy stories. Believing in God is like believing in the Flying Spaghetti Monster."
Ignoratio elenchi
- Proving something other than your point
- The "Today Programme" fallacy
- Use when: you are accused of something; use it to deny doing something else
"Isn't it true, Minister, that you have allowed the living standards of the poor to fall in real terms?"
"What we have done, Jim, is to increase by 3.7% the allowance to dependent females, and by 3.9% the allowance
to widows with two children, these increases both being larger than our opponents ever managed in a single year
of their term of office."
Argumentum ad populum
- Confusing the strength of numbers with the strength of the argument
- The "50 Million Frenchmen" fallacy
- Use to: support argument based on prejudice or preconception
- Play on emotions rather than building a case
"Walk up to 100 random people on the street, and ask them if they've heard of a video game, called Counterstrike. And if they have heard of it, have they played it. Now ask the same about Mario. Seriously, I know that Counterstrike is a good game, but apart from the people who do play it, most people have never even heard of it." -- "CastrTroy" on Slashdot, discussing which is the best game ever
Argumentum ad misericordiam
- An appeal to sympathy
- The "Cliff Richard" fallacy
- Use when: you want factors which should affect the punishment to affect the verdict
"What about those who have never heard the gospel, who don't even know that Jesus ever existed? Surely God will not send them to hell. That's unfair."
Post hoc ergo propter hoc
- If one thing follows another, there must be a causal link
- The "Lucky Underwear" fallacy
- Tip: Find somewhere the thing your opponent is arguing for has been tried, and claim that any subsequent bad effects were due to it
"Children who eat breakfast every morning tend to perform better at school" -- Jo Frost, Cornflakes box
"I really believe that the pagans, and the abortionists, and the feminists, and the gay and lesbians who are actively trying to make that an alternative lifestyle, the A.C.L.U., People for the American Way - all of them have tried to secularize America - I point the finger in their face and say, 'You helped this happen.'" -- Jerry Falwell, after Sept. 11th 2001
Poisoning The Well
- Disparaging your opponent in order to discredit his opinions
- Use when: your audience doesn't like your opponent, or is already prejudiced against his opinion
"Choice in education is only a device by which the middle classes can buy advantage for their children."
False Dichotomy
- Presenting only two possible choices when there are actually more
- The "War on Terror" fallacy
- Use to: channel opinion and make the "right" decision easy
- Tip: introduce the only possible choice by saying "There are two possible choices..."
You're either with us or against us in the fight against terror." -- George Bush
"Is it better to distribute DRMed media or no media at all?" -- Mass Debate participant
Your Turn...
"Kid, I've flown from one side of the galaxy to the other and I've seen a lot of strange stuff, but I've never seen anything that could make me believe there's one all-powerful force controlling everything." -- Han Solo
Argumentum ad ignorantiam
- Using lack of knowledge about something to conclude that the opposite is the case
- The "LUGRadio" fallacy
- Use when: you have bizarre views (e.g. a belief in UFOs); appeal to lack of evidence to the contrary
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Audio: The five best things about Britain, 1:05:10 - 1:05:27 ("Ubuntu vs. Debian")