Logic & Fallacies: Constructing a Logical Argument

[Anthile]

I figured some of you might like this.

http://www.infidels.org/library/modern/mathew/logic.html


Unfortunately, those who need it the most will never read it.

 

[Cognisant]

You're a poopy-head because I says so

This is now the amusingly stupid arguments thread.
Because Allah wills it.

 

[NoID10ts]

Good link.

Does anyone else find themselves reading these and thinking "if only insert name here would just read this", only to stop and think "oh shit, how many of these am I guilty of?"

That thought makes me want to quit debating anything for fear of looking like a total fool.

 

[AlisaD]

You're a poopy-head because I says so

This is now the amusingly stupid arguments thread.
Because Allah wills it.

The problem is that the rules of logic were, at one point, set in this exact manner.

It's easiest for me to discuss the rules of mathematical/boolean logic, because they are the ones closest to my way of thinking. And I also like bashing the basis of mathematics, because everyone just assumes they are true. No questions asked.

But honestly, mathematical logic is based on tautologies, statements or formulas which are considered to be true, because they are true.
Why? Because they always are.
How can I be sure? Because I said so.

 

[Cognisant]

It's a fishbowl thought but this thread isn't going anywhere anyway, I figure theism = 1, atheism = 0, satanism = -1, agnosticism = 1/0, and nihilism is of course a null value.

Satanism is awfully specific, the point I'm trying to convey is that -1 is the anti-value to theism's 1 value, I'm not actually doing maths here, just numerical representations of ideological stances. Atheism is interesting, it's a value of no value, like how in a computer a zero is a value just like any other, no different to one, two or three, even though to a human mind zero and a null value appear to be the same thing. The difference is that a null value isn't a value at all, its not numerical or anything else, its nothing, simply the absence of any data.

A true fishbowl thought, of no relevance or significance whatsoever.

 

[NoID10ts]

CARL SAGAN'S BALONEY DETECTION KIT

Based on the book The Demon Haunted World by Carl Sagan

The following are suggested as tools for testing arguments and detecting fallacious or fraudulent arguments:

• Wherever possible there must be independent confirmation of the facts
• Encourage substantive debate on the evidence by knowledgeable proponents of all points of view.
• Arguments from authority carry little weight (in science there are no "authorities").
• Spin more than one hypothesis - don't simply run with the first idea that caught your fancy.
• Try not to get overly attached to a hypothesis just because it's yours.
• Quantify, wherever possible.
• If there is a chain of argument every link in the chain must work.
• "Occam's razor" - if there are two hypothesis that explain the data equally well choose the simpler.
• Ask whether the hypothesis can, at least in principle, be falsified (shown to be false by some unambiguous test). In other words, it is testable? Can others duplicate the experiment and get the same result?

Additional issues are

• Conduct control experiments - especially "double blind" experiments where the person taking measurements is not aware of the test and control subjects.
• Check for confounding factors - separate the variables.

Common fallacies of logic and rhetoric

• Ad hominem - attacking the arguer and not the argument.
• Argument from "authority".
• Argument from adverse consequences (putting pressure on the decision maker by pointing out dire consequences of an "unfavourable" decision).
• Appeal to ignorance (absence of evidence is not evidence of absence).
• Special pleading (typically referring to god's will).
• Begging the question (assuming an answer in the way the question is phrased).
• Observational selection (counting the hits and forgetting the misses).
• Statistics of small numbers (such as drawing conclusions from inadequate sample sizes).
• Misunderstanding the nature of statistics (President Eisenhower expressing astonishment and alarm on discovering that fully half of all Americans have below average intelligence!)
• Inconsistency (e.g. military expenditures based on worst case scenarios but scientific projections on environmental dangers thriftily ignored because they are not "proved").
• Non sequitur - "it does not follow" - the logic falls down.
• Post hoc, ergo propter hoc - "it happened after so it was caused by" - confusion of cause and effect.
• Meaningless question ("what happens when an irresistible force meets an immovable object?).
• Excluded middle - considering only the two extremes in a range of possibilities (making the "other side" look worse than it really is).
• Short-term v. long-term - a subset of excluded middle ("why pursue fundamental science when we have so huge a budget deficit?").
• Slippery slope - a subset of excluded middle - unwarranted extrapolation of the effects (give an inch and they will take a mile).
• Confusion of correlation and causation.
• Straw man - caricaturing (or stereotyping) a position to make it easier to attack..
• Suppressed evidence or half-truths.
• Weasel words - for example, use of euphemisms for war such as "police action" to get around limitations on Presidential powers. "An important art of politicians is to find new names for institutions which under old names have become odious to the public"

 

[Anling]

I am convinced that that book needs to be required reading in school. I have this irrational hope that there would be less nonsense floating around if more people understood what sense was.

 

[NoID10ts]

I am convinced that that book needs to be required reading in school. I have this irrational hope that there would be less nonsense floating around if more people understood what sense was.

I agree, but those with not so clear thinking would never let it happen since so many of them are in positions of power. We can't have schools teaching kids to question things now can we?