In logic, a fallacy is not a false belief but a pattern of reasoning that is both typical and in some way specious. Specious reasoning, by the very etymology of the term, appears correct but is not. Thus a fallacy is not just any old mistake in reasoning, but a recurrent mistake that is seductive. A taxonomy of fallacies is useful insofar as it helps prevent one from seducing oneself and being seduced by others.
Second example. A: "Nowadays all chess players use algebraic notation." B: Not so, Ed Yetman does not use algebraic notation. He uses descriptive notation exclusively. A: Ed Yetman? You call him a chess player?!"
Third Example. A: "When a complete neuroscience is achieved, we will know everything about mind, brain, and consciousness." B: "I can't agree, even a completed neuroscience will not explain how consciousness arises from brain activity." A: "A neuroscience that can't explain consciousness would not be a completed neuroscience."
Fourth Example. A: "Theism ought to be combatted because theists have murdered and suppressed millions." B: "If so, then by the same token atheism should be combatted because in the 20th century alone atheistic Communists murdered 100 million people, suppressed even more and destroyed countless churches, synagogues, mosques, and temples." A: "But those murderers and destroyers are not true atheists, they don't represent us!"
Clearly, something has gone wrong in these examples. Person A is making an illicit dialectical move of some kind. The general form of the mistake seems to be as follows. Person A makes a universal assertion, one featuring a quantifier such as 'all,' 'no,' 'everything' whether explicit or tacit. Person B then adduces a counterexample to the universal claim. Person A illicitly dismisses the counterexample by modifying his original assertion with the use of 'true' or some equivalent designed to exclude the counterexample.
The fallacy is informal since the fallaciousness depends on the content or subject matter. So we need to ask: When is it not a fallacy? By my count, there are three classes of cases in which the No True Scotsman move is not fallacious.
1. When the original assertion is either a logical truth or an analytic truth. If I point out that all bachelors are male, and you reply that your sister Mary is a bachelor, then I am justified in dismissing your 'counterexample' by saying that Mary is not a true bachelor, or a bachelor in the strict sense of the term.
2. When the original assertion is synthetic but necessary. If Saul Kripke is right, 'Water is H2O' is synthetic but necessary. If I say that water is H2O, and you object that heavy water is not H2O but D2O, then I am entitled to respond that heavy water is not water.
3. When the original assertion involves stipulation. Suppose Smith defines a naturalist as one who denies the existence of God, and I respond that McTaggart is an atheist who is not a naturalist. Have I shown that Smith is wrong? Not all. Smith may respond that McTaggart is not a naturalist as she defines the term. Wholly or partially stipulative definitions cannot be said to be either true or false although they can be more or less useful for classificatory purposes. Second example. Suppose Jack claims that libertarians favor open borders and Jill responds by adducing the case of libertarian John Jay Ray who does not favor open borders. Jack is within his epistemic rights in saying that Ray is not a full-fledged libertarian.
Exercise for the reader: Provide more examples!
I would like to humbly submit that the fourth example may not apply.
Some Christians will respond to variations of your fourth example by saying, "The people in the Crusades and Inquisitions weren't true Christians!" Aside from being vague, their response probably intends to contrast Christian ethics with the behavior of the persons in question. I assume the atheist is aiming at the same target with his response.
So I'm seeing a few possible arguments, but since they're all modus ponens I'll just skip the connecting premise and conclusion for brevity's sake:
1) Blame the belief system
P1. If a belief system has a history of violence and oppression, it should be combatted.
2) Blame the belief system part 2
P1. If a belief system necessitates violence and oppression, it should be combatted.
3) Blame the believers, combat the belief system
P1. If believers participate in violence and oppression, their belief system should be combatted.
4) Blame the believers, combat the believers
P1. If believers participate in violence and oppression, they should be combatted.
I think the Scotsman fallacy would happen if you were defending against 3) or 4). Usually it seems like 2) is what atheists try to pin on religion (especially Islam). 1) seems pretty hard to justify, and 4) is hardly controversial.
Anyways there is my best shot. Thoughts anyone?
Posted by: David Parker | Thursday, February 26, 2009 at 08:36 PM
I don't think there is any problem with validity here. This argument
No Scotsman puts sugar in his porridge
Angus puts sugar in his porridge
Therefore, Angus is not a Scotsman
is clearly valid. And so is this:
No true Scotsman puts sugar in his porridge
Angus puts sugar in his porridge
Therefore, Angus is not a true Scotsman
Of course the argument is invalid if we omit 'true' in the premiss but not in the conclusion. But in any case the problem is not really about validity, but about soundness. What is a 'true Scotsman'? What is a 'true Christian'. If we cannot agree on the definition of that, we cannot agree on whether the minor premiss is true or not.
"For the entryway to wisdom is accessible to no one not educated in logic."
Posted by: ocham | Friday, February 27, 2009 at 08:20 AM
Bill,
Here's another class of case:
4. Where the presence or abscence of the fact described in the response is probabilistically relevant to determining the truth of the original assertion.
For instance, suppose that included in the accepted notion of what it is to be Christian is the idea of a supernaturally implanted desire for the good such that anyone who is a Christian is unlikely to commit grevious wrongs. Suppose I claim as much. My interlocuter responds that he saw Fred - someone we both know who professes to be a Christian - cutting up his neighbour with a chainsaw yesterday. I would be justified in responding that Fred (probably) wasn't truly a Christian. What has happened here is that the original predicate was partly defined probabilistically, and the otherwise good reasons for thinking a case to be a genuine counterexample (Fred claims he is a Christian, etc.) have been outweighed when assessed by the standards implied in the original assertion.
Matt.
Posted by: Matt Hart | Friday, February 27, 2009 at 08:29 AM
I think both Matt and ocham's posts are taken into consideration by Bill's comments on stipulation. And ocham is right in saying that then we need to query the stipulation. Grayling's comments in the Plantinga/Dennett post below are particularly egregious in this respect. He contrasts religious and atheist mindsets without making any reference to the fact that he might be using the latter as a term of art, and then responds to 'tu quoque' arguments by claiming that it is part of this definition of atheists that they do not follow One Big Idea (hence they are not true atheists). This makes several questionable assumptions: (i) it is not clear that everyone, including atheists, would agree with this stipulative definition (such as Stalin), (ii) it is not clear that some religious people might not be happy to apply this stipulative definition to themselves (such as pluralists), (iii) the wholesale eschewing of One Big Idea might be an example of One Big Idea. Furthermore, Grayling, although claiming that he is offering only examples of extreme religious institutions (such as the Taliban), actually provides another contentious stipulative definition, this time of religion, when he says that they are 'by nature' coercive and prone to violence. Hence he can say that any example adduced against this view is an example of 'no true religion'. Given this, Grayling's presentation of historical case studies and calls for counterexamples are a disingenuous smokescreen - he has already, through his stipulative definitions (which almost all neutral parties would reject, and which I think he will have trouble in trying to make stick) decided the issue in his favour on logical grounds. My own criticisms of Grayling were an attempt to get him to look at his definitions and see if they stood up.
Posted by: n--blog | Friday, February 27, 2009 at 10:10 AM
n-blog,
My class of case can't be covered under stipulation for my hypothesis takes it as analytically true that Christians have a tendency not to commit grievous wrongs.
Matt.
Posted by: Matt Hart | Friday, February 27, 2009 at 12:18 PM
O,
I didn't say there was any problem with validity. I indicated clearly in the second paragraph that the fallacy is informal. Surely you are familiar with the distinction between formal and informal fallacies. Petitio principii is an informal fallacy but is as valid as can be.
Posted by: Bill Vallicella | Friday, February 27, 2009 at 12:50 PM
Dear Matt,
Re-reading your post, I have absolutely no idea why I mentioned it as a case of stipulation. You are quite right, and I do apologise.
Best,
N
Posted by: n--blog | Friday, February 27, 2009 at 06:52 PM
n--blog,
Actually it was you who gave me the idea of relabelling the No True Scotsman as the No True Atheist, when the latter is really an instance of the former.
Posted by: Bill Vallicella | Friday, February 27, 2009 at 07:10 PM
>>Surely you are familiar with the distinction between formal and informal fallacies. Petitio principii is an informal fallacy but is as valid as can be.
I'm not sure I agree with this. The distinction between formal and informal fallacy is not the same as the distinction between logical (invalid) and material (unsound) fallacy. The two material fallacies are petitio and elenchi, according to Whately.
Some writers (e.g. Joseph) refuse to admit material fallacies at all, since a fallacy by definition involves a fault in reasoning, a failure of the premises to support the conclusion.
Posted by: ocham | Saturday, February 28, 2009 at 02:25 AM
I'm not sure I've ever heard someone say "but they weren't true atheists" regarding e.g. Stalin. Even Dawkins and Harris readily admit that Stalin was as true an atheist as one could ask for. I think the argument is generally that Stalin's atheism is irrelevant to his actions, and therefore his actions are irrelevant to the merits of atheism.
This is in marked contrast to defenders of Christianity with regard to the Crusades, who usually do admit that the Crusaders were motivated by their interpretation of Christianity, but argue that their interpretation was incorrect. That's a true Scotsman.
Posted by: A. Cooper | Wednesday, March 04, 2009 at 05:10 PM
A. Cooper,
I am not seeing how the Scotsman fallacy is being used to defend the Crusades with respect to interpretations of Christianity. If you don't mind, would you formally notate that?
Sorry I am practicing my critical thinking skills, so it helps to see what you're thinking rather than assume my reconstruction is what you intended.
Thanks!
Posted by: David Parker | Wednesday, March 04, 2009 at 07:56 PM
I'm not sure the good of formally notation in showing an informal fallacy (and indeed, I'm agnostic on whether formal notation as it's ordinarily used in philosophy helps much even to settle formal questions). I'll give it a go, but with tongue firmly planted in cheek.
Let's denote by L the proposition "They will know you're a Christian by your love," by C1 the proposition "The Crusades were not loving," and by C2 "The Crusades were motivated by Christian belief."
C1 and C2 are generally accepted, and Christians assert L. One can resolve the apparent contradiction by changing "Christian belief" to "true Christian belief"; this new proposition C2' is often denied while accepting C2. Doing so allows one to retain the label "Christian" for things like papal edicts, sermons in churches, etc., while at the same time distancing oneself from unsavory acts.
That's exactly the True Scotsman situation.
Posted by: A. Cooper | Wednesday, March 04, 2009 at 09:31 PM