Tag: Logic

I’m sidestepping Fischer and Newall for a moment to focus on one instance of a fallacy that both of them seem to have overlooked. It as one type of an “appeal to authority”.

[M]ost people do not have a sufficient background in the subject to properly evaluate the evidence. Anti-Stratfordians [those questioning the authorship of Shakespeare’s plays] tend to be amateurs who have not read enough on Elizabethan theatre to see just how wildly implausible their ideas are. Let me give you an analogy. I can recognise the difference between a Yorkshire and Lancashire accent without very much trouble because I am English. I would never mistake an Irishman for a Scotsman. On the other hand, when I was living in New Jersey, I was frequently assumed to be Irish and had no idea that Californians sound different to Texans. Distinguishing accents isn’t something you tend to be taught. Rather you learn it by experience and by being immersed in a particular culture. It’s the same with history. If you have been studying a period for long enough, ideas like the anti-Stratfordians’ are as obviously incongruous as a baseball bat on a cricket pitch. (Hannam, xii)

The Latin label of that fallacy of appealing to authority is argumentum ad verecundiam. Verecundiam means shame or modesty; the idea being that an appeal to authority is an acknowledgement that the one making the argument lacks the expertise but modestly defers to another who is an expert. There is nothing modest about the above appeal, however. Yet it does demand modesty on the part of anyone who disagrees.

I found the following online explanation the most apt description where it is called Appeal to Confidence:

The arguer supports a position by appealing to himself as knowledgeable or trustworthy on the given subject, while at the same time declining to explain the actual reasons for a position. . . . 

The argument appeals to confidence-building phrases, such as “trust me,” or “take it from me,” or makes an explicit claim to authority, such as “I know what I’m talking about.” 

The historian who wrote that passage claiming that a historian “just knows” by being immersed in the field what is a valid argument and what is not is James Hannam (also author of God’s Philosophers). The difference between a valid and invalid idea cannot always be taught? That’s what he is saying there and it is perhaps relevant that he is not speaking of those who question whether Shakespeare wrote his plays but whether Jesus existed or not. The passage is from James Patrick Holding’s Shattering the Christ Myth. Hannam is the only professional historian contributing to that volume.

Hannam speaks of “experience” and “immersion in a particular culture”. That is indeed the critical factor. It is that sort of background that makes unquestioned assumptions so hard to identify and pull out for serious examination.

As for “cultural immersion” being a solid basis for identifying an anomalous argument, Hannam is clearly unaware of a growing number of biblical scholars (still a minority, of course) who do not consider the Jesus myth idea so “incongruous” as he suggests.

“Appeal to Confidence.” 2019. Bruce Thompson’s Fallacy Page. September 2019. https://www2.palomar.edu/users/bthompson/Appeal%20to%20Confidence.html.

Hannam, James. 2008. “A Historical Introduction to the Myth That Jesus Never Existed.” In Shattering the Christ Myth, edited by James Patrick Holding, xi–xvii. Xulon Press.

A false dilemma is seen whenever only two possible options are given when there exist others. (This fallacy is also known as a false dichotomy). For example, a person might insist, “you’re either with me or against me” and hence force the listener to join forces or else be taken as an enemy. In general, we have the following:

P1: Either A or B;

P2: Not A;

C: Therefore, B.

The argument seems valid but a premise is missing; namely, something like “P3: No other options other than A and B exist.” It is often used for rhetorical effect; after all, if only two choices are available and one is unpalatable then we are forced to choose the other, even if we might otherwise have reservations.

(Newall, 264)

Some historians have fallen into this fallacious reasoning when addressing Neville Chamberlain’s responses to Hitler. Essentially the argument has been:

P1: Chamberlain had the option to either [A] stand up to Hitler and prevent war or [B] appease him and lead to further demands and world war.

P2: Chamberlain did not [A] stand up to Hitler and prevent war.

C: Therefore, [B] Chamberlain is to be blamed for making the cowardly choices that led to war.

What is missing are other “dilemmas” facing Chamberlain:

or C: Chamberlain believed Russia was a serious threat and believed Hitler would invade east, not west.

or D: Chamberlain feared Japan and Italy would take advantage of Britain being tied down with Germany to overrun British interests in Asia and the Mediterranean.

or E: Chamberlain knew Britain would not tolerate another war given their fresh memories of the horrors of the last one.

As summed up by Paul Newall: Continue reading “Logical Fallacies of Historians: the False Dilemma (Dichotomy)”

The fallacy of the circular proof is a species of a question-begging, which consists in assuming what is to be proved. . . . [I]t is exceedingly common in empirical scholarship. (Fischer, 49)

Begging the question (or petitio principii) occurs when the conclusion of an argument is used to demonstrate it, thereby achieving a circular proof. (Newall, 264)

Fischer offers a silly example to illustrate.

A researcher asks, “Do gentlemen prefer blondes?” He discovers that Smith, Jones, and James prefer blondes, and tacitly assumes that Smith, Jones, and James are therefore gentlemen. He concludes that three gentlemen out of three prefer blondes, and that the question is empirically established, with a perfect correlation. His argument runs through the following stages :

Inquiry : Do gentlemen prefer blondes?

Research : Smith, Jones, and James prefer blondes.

(Tacit Assumption) : Smith, Jones, and James are gentlemen.

Conclusion: Therefore, gentlemen prefer blondes.

Here are some other examples I’ve considered. Let me know if I have made mistakes or if you have others to add.

Inquiry: Has Trump been a good manager of the US economy?

Research: The GDP has increased under Trump’s presidency.

(Tacit Assumptions): Trump’s policies have been responsible for its growth and there are no negatives in the economy that outweigh the positive figures.

Conclusion: Therefore, Trump has been a good manager of the US economy.

– – – o – – –

Inquiry: Should Trump encourage people to try hydroxychloroquine as a cure for COVID-19?

Research: Trump and others say they have heard that many people have tried it and been cured of COVID-19.

(Tacit Assumption): The stories one has heard are all genuine and hydroxychloroquine was responsible for the cures and there have been no negative experiences with hydroxychloroquine.

Conclusion: Therefore, Trump should encourage people to try hydroxychloroquine as a cure for COVID-19.

– – – o – – –

Inquiry: Is the lockdown response an overreaction to the COVID-19 threat?

Research: I and other people I know are sensible and will keep social distancing advice without a lockdown.

(Tacit Assumption): the lockdown is an overreaction because everyone is like me and we can contain the COVID-19 spread without a lockdown

Conclusion: Therefore, the lockdown is an overreaction.

– – – o – – –

Inquiry: Is it a historical fact that Judas betrayed Jesus?

Research: It is unthinkable that the early church would make up a story of one of the inner Twelve betraying Jesus.

(Tacit Assumption): There was a historical Jesus with a historical Twelve disciples whom he trusted and the early church was dedicated to recording the historical facts.

Conclusion: Therefore it is a historically reliable tradition that Judas betrayed Jesus.

– – – o – – –

Inquiry: Did Jesus exist?

Research: No Jew would have made up a story about a crucified itinerant preacher being the Davidic messiah.

(Tacit Assumption): Jesus was historically an itinerant preacher who was crucified yet still believed by his followers to be the Davidic messiah.

Conclusion: Jesus existed. Continue reading “Logical Fallacies of Historians: Begging the Question”

If your theory explains the evidence does that mean it is probably correct? If “everything fits”, is your theory therefore surely right?

There’s a problem with that way of thinking and it is taken head-on by Paul Newall in a chapter titled “Logical Fallacies of Historians” in Tucker and Kane’s A Companion to the Philosophy of History and Historiography.

Affirming the consequent is a formal fallacy occurring when one or more potential premises are omitted from an argument. For example, “if my rain dance worked then it should be raining; it is raining; therefore, my rain dance worked.” Here other possible causes of the rainfall are left out and the argument fails. Affirming the consequent has the general form:

P1: If A then B;

P2: B;

C: Therefore, A.

(Newall, 263)

Some of you may know of a 1970 “classic” by David Hackett Fischer, Historians’ Fallacies: Toward a Logic of Historical Thought. Newall acknowledges the strength of Fischer’s work but in a single chapter is addressing what he sees as the most common and unfortunately enduring fallacies among historians.

So how can one guard against being overcome by this fallacy? Newall continues:

However, we can add missing premises to show the error:

P1a: If C then B;

P1b: If D then B;

. . . and so on. For an argument of this form to not be fallacious, we would need an additional premise stating that A is the only possible cause of B. (Note that affirming the antecedent (or modus ponens) is not fallacious; that is, arguing “if A then B; A; therefore, B.”)

This fallacy is of considerable importance to historiography because it often forms the basis of models of confirmation and shows why a more sophisticated philosophical apparatus is required. A typical statement might be: “if our model/explanation of x [some event, say] is correct, we would expect to find y [some evidence, records or traces, for instance], as indeed we do.” Thus an account of some historical episode predicts that certain evidence of it will be found, and when this happens the account is confirmed or demonstrated to be correct. However, in this form the account is straightforwardly fallacious as an example of affirming the consequent.

For example, if Einstein were an extraterrestrial of superior intelligence, he should have made incredible intellectual achievements. He did, and therefore he was an extraterrestrial. We can attempt to undercut this objection by arguing that actually the evidence only makes the account more likely, but this requires further elaboration before it becomes philosophically tenable, for example by comparing different hypotheses with different prior probabilities (see Tucker 2004, for an example of a Bayesian approach that avoids this difficulty).

Bayes? Yes, historians use Bayes.

I’ve been trying to think through some other examples. Here are a few. Two political ones to start followed by some biblical ones, including some mythicist examples. Continue reading “Logical Fallacies of Historians: “If It Fits — Be Careful!””