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The main subject we should've had in school. We would've caught on the reading and writing at some point anyway. Absolutely hilarous too. Wishing I was friends with the author. (the mitochondrion is the powerhoure of the cell)

Affirming the consequent

When cats are bitten by rabid hedgehogs they die. Here is a dead cat, so obviously there is a rabid hedgehog about.


I met the ambassador riding his horse. He was snorting and steaming, so I gave him a lump of sugar.

The analogical fallacy

She had skin like a million dollars.

Antiquitam, argumentant ad

You are not having a car. I never had a car, my father never had on and nor did his father before.


Beliefs have little to do with reality

We don't need to look through your telescope, Mr Galileo. We know there cannot be more than seven heavenly.

All doctors are in it for themselves. If yours really did give up all that t for no payment, then all I can say is that there must have been some hidden gain we don't know about.

Baculum, argumentum ad

Unpleasant consequences are promised for failing to comply with the speaker's wishes.

It would be better if you told us what we want to know. After all, we wouldn't want your aged mother or your crippled sister to suffer, would we?


Present only two alternatives when there are many.

If you are not with us, you are against us.

There are two types of people in this world: the rich and the suckers. Do you want to get rich, or are you happy to remain a sucker?

Blinding with science

The amotivational syndrome issustained by peer group pressure except where achievement orientation forms a dominant aspect of the ed tional and social milieu.

The bogus dilemma

Don't do it. If you tell the truth men will hate you, and if you tell lies gods will hate you. Since you must either tell the truth or tell lies, must be hated either by men or by the gods.

I shall do it, mother. For if I tell lies, men will love me for it; and if I tell truth the gods will love me. Since I must tell truth or lies, I shall be beloved of men or gods.

Cireulus in probando

It consists of using as evidence a fact which is authenticated by the very conclusion it supports.

I didn't do it, sir. Smith minor will vouch for my honesty.' 'Why should I trust Smith minor?' 'Oh, I can guarantee his honesty, sir.'

The complex question (plurium interrogationum)

Have you stopped beating your wife?

Is your stupidity inborn?


This must be a good orchestra because each of its members is a tale musician.

If everyone in society looks after themselves, then our society will be one that looks after itself.

Concealed quantification

Garage mechanics are crooks.

Have you ever noticed that bishops are fat? I suppose now that Joh has been raised to a bishopric he'll expand a bit himself.

Conclusion which denies premises

'Son, because nothing is certain in this world we have to hold on to w experience tells us. ' 'Are you sure, Dad?' 'Yes, son. I'm certain.'

Everything must have a cause. That, in turn, must result from a previ cause. Since it cannot go back for ever, we know that there must be uncaused causer to start the process.

Contradictory premises

Everything is mortal, and God is not mortal, so God is not everything.

He's a real professional, but a bit of an amateur at times.

Crumenam, argumentum ad

Assumes that money is a measure of Tightness, and that those with money are more likely to be correct.

I note that those earning in excess of £100,000 per year tend to agr with me.

Surely a man who can make £60 million in a year by recording four songs cannot be all wrong.

Cum hoc ergo propter hoc

Assumes that events which occur together are causally connected, and leaves no room either for coincidence, or for the operation of an outside factor which separately influences these events.

A tourist met a Spanish peasant and his wife on a train. They had never seen bananas before, so he offered one to each of them. As the farmer bit into his, the train entered a tunnel. 'Don't eat it, Carmen,' he shouted, 'They make you blind.'

Damning the alternatives

Hawkins' theory has to be the right answer. All the others have bee proved hopelessly wrong.

Chelsea isa really great team. Look at Liverpool and Manchester Unit they are both useless.

Definitional retreat

Someone changes the meaning of the words in order to deal with an objection raised against the original wording.

'He's never once been abroad.' 'As a matter of fact, he has been to Boulogne. ' 'You cannot call visiting Boulogne going abroad!'

'When I use a word,' Humpty Dumpty said in rather a scornful tone, 'it means just what I choose it to mean - neither more nor less.'

Denying the antecedent

If I eat too much, I'll be ill. Since I have not eaten too much, I will not be ill.

If I smoke, drink or have sex, it will shorten my life-span. I shall give cigars, booze and women and live another hundred years.

Dicto simpliciter

Sweeping generalisation applying to an individual case.

Of course you voted for the resolution. You're a dock-worker, and your union cast 120,000 votes in favour.

Everyone knows that hooded teenagers are criminals. Since this ho one isn't breaking any laws, he must be older than he looks.


The Icelanders are the oldest nation on earth. This means that Bjo must be older than other pop stars.

California is a very wealthy state, so if he comes from there he must worth quite a bit.

Emotional appeals

Let's be reasonable about this.

(a strong emotional appeal for the quiet life)


Using words ambiguously.

Happiness is the end of life. The end of life is death; So happiness is death.

You can rest assured that your letter will receive the attention it fully deserves. (in the bin)

Every schoolboy knows

'Everyone can see that...'

We hold these truths to be self-evident.

The exception that proves the rule

Medical advances are made by painstaking research, not by chance. I know there was penicillin, but everyone knows that was a chance in million.

'Lend us a fiver. I've always paid you back before.' 'What about last week?' 'That was the exception that proves the rule. You know you'll get it back in the long run.'

Exclusive premises

Some brewers are not idiots, and some idiots are not rich, so some brewers are not rich.

The existential fallacy

Statements that refer to a whole of a class do not actually tell us if there are any members of that class (all cats are selfish)while statements which tell us about some of a class, do imply the existence of members of the class (some cats are selfish).

If you just move to saying 'some' rather than 'all' you are much more likely to be convincing.

Ex-post-facto statistics

A mathematically precise line from an unwarranted assumption to a foregone conclusion.

I drew the ace of spades. It was only a 1 in 52 chance, but it came up.

(it was 1/52 for every other card)

I met my aunt in Trafalgar Square on Wednesday. Think of the hund of thousands going through the square that day, and you'll realize h unlikely it was that we should meet there. Maybe we are telepathic.

(the same applies to the thousands of other people you met)

Extensional pruning

All we said was that we'd install a switchboard. We didn't say it would work.

I said I'd get you another drink if I was wrong: water is another drink.

False conversion

All rats are four-legged animals, so obviously all four-legged animals are rats.

We can make statements about:

  1. All are

  2. Some are

  3. None are

  4. Some are not

You can only swap 2 and 3 and not 1 and 4.

So you can say: Some As are Bs - Some Bs are As No As are Bs - No Bs are As

But you can't say: All As are Bs - All Bs are As Some As are not Bs - Some Bs are not As

Since we know that some Marxists are not school-teachers, it follows it some school-teachers are not Marxists.

False precision

Exact numbers are used for inexact notions.

People say the Scots are mean, but they have been shown in surveys be 63 per cent more generous than the Welsh.

The gambler's fallacy

Red has come up 73 times out of the last 20. That means we are due for a run of blacks. I am betting on black.

The genetic fallacy

Giving less credence to views which eminate from those they detest, regardless of the actual merit of the views themselves.

Don't be obsessed with punctuality. It was Mussolini who wanted trains to run on time.

Half-concealed qualification

The words themselves express a limited claim, but the stress and construction is such that the qualifications are glossed over.

Practically every single case of monetary expansion is followed within months by an attendant general price rise of the same proportions.

Palm trees don't normally grow in England, so it must be something.


Sheltering behind ambiguous meanings so that the sense can be changed later.

'All I said was that I'd be home at a reasonable hour. I think that three o'clock in the morning is a reasonable hour in view of what I've been doing.'

Hominem (abusive), argumentum ad

Dr Green argues very plausibly for fluoridation. What he does not te is that he is the same Dr Green who ten years ago published article favour of both euthanasia and infanticide.

Hominem (circumstantial), argumentum ad

You can't accept the legitimacy of lending for profit. You are a Christian, and Christ drove the money-lenders from the temple.

Ignorantiam, argumentum ad

Using lack of knowledge to infer its opposite is the case

Ghosts exist all right. Research teams have spent many years and millions of pounds attempting to prove that they don't; and they have not succeeded.

Ignoratio elenchi

When someone believes themselves to be proving one thing but proves another.

I shall oppose this measure to permit people to leave school earlier by proving once again the value of education.

How could my client have ordered the murder? I have proved beyond a shadow of doubt that he was not even in the country at the time.

Illicit process

All tax-collectors are civil servants, and all tax-collectors are bullies, civil servants are bullies.

Irrelevant humour

My opponent's position reminds me of a story...

Lapidem, argumentum ad

He's a friend of mine. I won't hear a word spoken against him.

Reason is no guide; you must open your heart... and you will know.

Lazarum, argumentant ad

It is a fallacy to suppose that because someone is poor that they must be sounder or more virtuous than one who is rich.

The guru has nothing to gain by lying or fooling anyone; all he has are the nuts that he lives on.

The best view I ever heard on this was told to me by a simple, honest woodcutter...

Loaded words

The deliberate use of prejudiced terms.

Once again Britain has been found sucking up to dictatorships.

Misericordiam, argumentum ad

The use of pity as an argument.

In asking yourself if this man is to be convicted, ask yourself what i mean for him to be locked up in prison, deprived of his liberty, a turned into an outcast from humanity.

Nauseam, argumentum ad

Uses constant repetition, often in the face of massive evidence against a contention, to make it more likely to be accepted.

Just the place for a Snark! I have said it thrice; what I tell you three tim is true.

It washes whiter than bleach; that's whiter than bleach; yes, whiter bleach.


If tobacco really is so harmful, how come people didn't ban it years ago?

If breakfast television is all that good, why has it taken so long for it to appear?

Novitam, argumentum ad

It is fallacious to suppose something to be more right simply because it is new.

These new tower-blocks are the coming thing. We should build some ourselves.

Numeram, argumentum ad

Fifty million Frenchmen can't be wrong!

We have to give him a fair trial before we string him up. All those who say he did it shout 'aye!'

If it's not true, then why have so many millions of people believed in it for so many centuries?

One-sided assessment

This encyclopedia is one you will be proud to own. Your friends w admire it. Your children will benefit. You will learn from it. It will complement your bookshelf.

Let's not go to Ibiza. Think of the heat, the mosquitoes and the crowds.

Petitio principii

Use is made in the argument of something which the conclusion seeks to establish.

Justice requires higher wages because it is right that people should earn more.

We should not sell arms to Malaysia because it would be wrong for equip other nations with the means of taking human life.

(This looks and sounds like an argument, but it is really just a clever way of saying that we should not sell arms to Malaysia because we should not sell arms to anyone.)

Poisoning the well

Making unpleasant remarks about anyone who might disagree with a chosen position.

Everyone except an idiot knows that not enough money is spent on education.

Populum, argumentum ad

Appeals to popular attitudes instead of presenting relevant material.

In recommending Higginbottom, I'd point out that the smart mone on him.

If we allow the corner shop to close, it will mean hard-earned money going out of the community to rich businessmen in flash cars. The corner shop is part of our locality; it's a friendly presence in the neighbourhood; it's the focal point of the community we grew up in.

(People will do anything for it, except shop there.)

Positive conclusion from negative premise

Some cats are not stupid, and all cats are animals, so some animals are stupid.

(the premise is negative, so the conclusion must also be for it to be valid)

Post hoc ergo propter hoc

Immediately after the introduction of canned peas, the illegitimate birthrate shot up to a new high from which it did not decline until frozen peas edged canned peas out of the market. The link is all too obvious.

Quaternio terminorum

The four term fallacy arises where a statement is disguised as a three term - middle one disappears - statement

John is to the right of Peter, and Peter is to the right of Paul, so John is to the right of Paul.

(Here we have Term 1: John; Term 2: right of Peter; Term 3: Peter; Term 4:right of Paul - so it is not a 3 statement conclusion eg can be a round table)

More obvious: John is the father of Peter, and Peter is the father of Paul, so John is the father of Paul.

The red herring

The fallacy of the red herring is committed whenever irrelevant material is used to divert people away from the point being made, and to pro- ceed towards a different conclusion.

'The police should stop environmental demonstrators from inconveniencing the general public. We pay our taxes. ' 'Surely global meltdown is infinitely worse than a little inconvenience?'

'Excuse me, sir. What are you doing with that diamond necklace h out of your pocket?' 'I say, isn't that a purebred German shepherd dog you have w

Refuting the example

'Teenagers are very bad-mannered these days. That boy from next d nearly knocked me over in the street yesterday, and didn't even stay apologize. ' 'You're wrong. Simon is no longer a teenager.'


Also called hypostatization, consists in the supposition that words must denote real things. Because we can admire the redness of a sunset, we must not be led by the exist- ence of the word into supposing that redness is a thing. When we see a red ball, a red table, a red pen and a red hat, we commit the fallacy of reification if we suppose that a fifth object, redness, is present along with the ball, the table, the pen and the hat.

In SKYROS we have extracted the blueness of the summer sky and inserted it in a bar of heavenly soap.

He realized that he had thrown away his future, and spent the rest of the afternoon trying to find it again.

The runaway train

An argument used to support a course of action would also support more of it.

The state should subsidize opera because it would be too expensive mount productions without the extra support from public

You agreed to allow a bingo hall in the town because people should the choice to gamble if they want to. I'm now proposing to have gam machines on every street corner for precisely the same reason.

Secundum quid

Hasty generalisation.

I was in Cambridge for ten minutes and I met three people, all drunk. The whole place must be in a state of perpetual inebriation.

Shifting ground

When people do shift the substance of what they were saying.

I said I liked the project and thought it a good one. However, I share the objections you have all voiced, and can only say how much this rein- forces a view I have long held that it is not enough for a project to be likeable and good.

Shifting the burden of proof

It consists of putting forward an assert- ion without justification, on the basis that the audience must disprove it if it is to be rejected.

'Schoolchildren should be given a major say in the hiring of their teachers. ' 'Why should they?' 'Give me one good reason why they should not. '

I believe that a secret conspiracy of llluminati has clandestinely direct world events for several hundred years. Prove to me that it isn't so.

The slippery slope

I oppose lowering the drinking age from 21 to 18. This will only lead to further demands to lower it to 16. Then it will be 14, and before we know it our newborns will be suckled on wine rather than mother's milk.

Special pleading

Our attempt to engage in conversation was totally spoiled by all the chattering that other people were doing.

While it is not normally right to invade someone's privacy, it is all right for us, as journalists, to do so because we serve a public need.

The straw man

A misrepresentation of your opponent's position created for the express purpose of being knocked down.

'We should liberalize the laws on marijuana.' 'No. Any society with unrestricted access to drugs loses its work ethic goes only for immediate gratificatication.'

How can we support the Democrats when one of their own union backers publicly advocates a 'worker state' like Soviet Russsia was?

Temperantlam, argumentum ad

The moderate view is the correct one, regardless of its other merits.

The unions have asked for 6 per cent, the management have offere per cent. Couldn't we avoid all the hardship and waste of a length strike, and agree on 4 per cent?

Thatcher's blame

Blame is attached no matter the outcome.

I've been asked to a christening, but I'm sure they'll give the child some outlandish name that will make it a laughing-stock. Either that or some unbelievably tedious and commonplace name which will make the c seem like a faceless conformist.

Trivial objections

I am totally opposed to the new road around the town. It will make a our town maps out of date.

Tu quoque

The proponent is himself guilty of what the talks of.

Why should we listen to Brown's support for the new carpark when only last year he opposed the whole idea?

Unaccepted enthymemes

Bill must be stupid. You have to be stupid to fail a driving-test.

*I hope to repay the bank soon, Mr Smith. My late aunt said she would leave a reward to everyone who had looked after her. (*but you didn't take care of her)

Darling, I'm sorry. Busy people tend to forget such things as anniversaries. (but you're not busy)

The undistributed middle

All men are mammals. Some mammals are rabbits, therefore som are rabbits.

All nurses are really great people, but it happens that some really gr people are not properly rewarded. So some nurses are not proper rewarded.

Unobtainable perfection

We should ban the generation of nuclear power because it can never be made completely safe.

I'm against going to the Greek islands because we cannot guarantee we would enjoy ourselves there.

Verecundiam, argumentum ad

Hundreds of leading scientists reject evolution. (Not those who sepecialise in evolutionary biology)

Wishful thinking

Of course the environment talks will succeed. Otherwise it means man- kind is on the way out.



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