Introduction

Welcome to Tim Harding’s blog of writings and talks about logic, rationality, philosophy and skepticism. There are also some reblogs of some of Tim’s favourite posts by other writers, plus some of his favourite quotations and videos This blog has a Facebook connection at The Logical Place.

There are over 2,300 posts here about all sorts of topics – please have a good look around before leaving.

If you are looking for an article about Skepticism, Science and Scientism published in The Skeptic magazine titled ”A Step Too Far?’, it is available here.

If you are looking for an article about the Birth of Experimental Science published in The Skeptic magazine titled ‘Out of the Dark’, it is available here.

If you are looking for an article about the Dark Ages published in The Skeptic magazine titled ‘In the Dark’, it is available here.

If you are looking for an article about the Traditional Chinese Medicine vs. Endangered Species published in The Skeptic magazine titled ‘Bad Medicine’, it is available here.

If you are looking for an article about the rejection of expertise published in The Skeptic magazine titled ‘Who needs to Know?’, it is available here.

If you are looking for an article about Charles Darwin published in The Skeptic magazine titled ‘Darwin’s Missing Link“, it is available here.

If you are looking for an article about the Astronomical Renaissance published in The Skeptic magazine titled ‘Rebirth of the Universe‘, it is available here.

If you are looking for an article about DNA and GM foods published in The Skeptic magazine titled ‘The Good Oil‘, it is available here.

If you are looking for an article about animal welfare published in The Skeptic magazine titled ‘Creature Features‘, it is available here.

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What is logic?

The word ‘logic‘ is not easy to define, because it has slightly different meanings in various applications ranging from philosophy, to mathematics to computer science. In philosophy, logic’s main concern is with the validity or cogency of arguments. The essential difference between informal logic and formal logic is that informal logic uses natural language, whereas formal logic (also known as symbolic logic) is more complex and uses mathematical symbols to overcome the frequent ambiguity or imprecision of natural language. Reason is the application of logic to actual premises, with a view to drawing valid or sound conclusions. Logic is the rules to be followed, independently of particular premises, or in other words using abstract premises designated by letters such as P and Q.

So what is an argument? In everyday life, we use the word ‘argument’ to mean a verbal dispute or disagreement (which is actually a clash between two or more arguments put forward by different people). This is not the way this word is usually used in philosophical logic, where arguments are those statements a person makes in the attempt to convince someone of something, or present reasons for accepting a given conclusion. In this sense, an argument consist of statements or propositions, called its premises, from which a conclusion is claimed to follow (in the case of a deductive argument) or be inferred (in the case of an inductive argument). Deductive conclusions usually begin with a word like ‘therefore’, ‘thus’, ‘so’ or ‘it follows that’.

A good argument is one that has two virtues: good form and all true premises. Arguments can be either deductiveinductive  or abductive. A deductive argument with valid form and true premises is said to be sound. An inductive argument based on strong evidence is said to be cogent. The term ‘good argument’ covers all three of these types of arguments.

Deductive arguments

A valid argument is a deductive argument where the conclusion necessarily follows from the premises, because of the logical structure of the argument. That is, if the premises are true, then the conclusion must also be true. Conversely, an invalid argument is one where the conclusion does not logically follow from the premises. However, the validity or invalidity of arguments must be clearly distinguished from the truth or falsity of its premises. It is possible for the conclusion of a valid argument to be true, even though one or more of its premises are false. For example, consider the following argument:

Premise 1: Napoleon was German
Premise 2: All Germans are Europeans
Conclusion: Therefore, Napoleon was European

The conclusion that Napoleon was European is true, even though Premise 1 is false. This argument is valid because of its logical structure, not because its premises and conclusion are all true (which they are not). Even if the premises and conclusion were all true, it wouldn’t necessarily mean that the argument was valid. If an argument has true premises and its form is valid, then its conclusion must be true.

Deductive logic is essentially about consistency. The rules of logic are not arbitrary, like the rules for a game of chess. They exist to avoid internal contradictions within an argument. For example, if we have an argument with the following premises:

Premise 1: Napoleon was either German or French
Premise 2: Napoleon was not German

The conclusion cannot logically be “Therefore, Napoleon was German” because that would directly contradict Premise 2. So the logical conclusion can only be: “Therefore, Napoleon was French”, not because we know that it happens to be true, but because it is the only possible conclusion if both the premises are true. This is admittedly a simple and self-evident example, but similar reasoning applies to more complex arguments where the rules of logic are not so self-evident. In summary, the rules of logic exist because breaking the rules would entail internal contradictions within the argument.

Inductive arguments

An inductive argument is one where the premises seek to supply strong evidence for (not absolute proof of) the truth of the conclusion. While the conclusion of a sound deductive argument is supposed to be certain, the conclusion of a cogent inductive argument is supposed to be probable, based upon the evidence given. An example of an inductive argument is: 

Premise 1: Almost all people are taller than 26 inches
Premise 2: George is a person
Conclusion: Therefore, George is almost certainly taller than 26 inches

Whilst an inductive argument based on strong evidence can be cogent, there is some dispute amongst philosophers as to the reliability of induction as a scientific method. For example, by the problem of induction, no number of confirming observations can verify a universal generalization, such as ‘All swans are white’, yet it is logically possible to falsify it by observing a single black swan.

Abductive arguments

Abduction may be described as an “inference to the best explanation”, and whilst not as reliable as deduction or induction, it can still be a useful form of reasoning. For example, a typical abductive reasoning process used by doctors in diagnosis might be: “this set of symptoms could be caused by illnesses X, Y or Z. If I ask some more questions or conduct some tests I can rule out X and Y, so it must be Z.

Incidentally, the doctor is the one who is doing the abduction here, not the patient. By accepting the doctor’s diagnosis, the patient is using inductive reasoning that the doctor has a sufficiently high probability of being right that it is rational to accept the diagnosis. This is actually an acceptable form of the Argument from Authority (only the deductive form is fallacious).

References:

Hodges, W. (1977) Logic – an introduction to elementary logic (2nd ed. 2001) Penguin, London.
Lemmon, E.J. (1987) Beginning Logic. Hackett Publishing Company, Indianapolis.

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Reasoning

Rationality may be defined as as the quality of being consistent with or using reason, which is further defined as the mental ability to draw inferences or conclusions from premises (the ‘if – then’ connection). The application of reason is known as reasoning; the main categories of which are deductive and inductive reasoning. A deductive argument with valid form and true premises is said to be sound. An inductive argument based on strong evidence is said to be cogent. It is rational to accept the conclusions of arguments that are sound or cogent, unless and until they are effectively refuted.

A fallacy is an error of reasoning resulting in a misconception or false conclusion. A fallacious argument can be deductively invalid or one that has insufficient inductive strength. A deductively invalid argument is one where the conclusion does not logically follow from the premises. That is , the conclusion can be false even if the premises are true. An example of an inductively invalid argument is a conclusion that smoking does not cause cancer based on the anecdotal evidence of only one healthy smoker.

By accident or design, fallacies may exploit emotional triggers in the listener (e.g. appeal to emotion), or take advantage of social relationships between people (e.g. argument from authority). By definition, a belief arising from a logical fallacy is contrary to reason and is therefore irrational, even though a small number of such beliefs might possibly be true by coincidence.

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A Different Take on E.O. Wilson

Reblogging does not necessarily entail endorsement.

Massimo Pigliucci

by Massimo Pigliucci

Here is a Roman joke: Two old friends who haven’t seen each other in a while happen to meet in the street. One says to the other: “Oh, hi! I thought you were dead!”

“What on earth makes you say so?”

“Well, all of a sudden people were speaking well of you …”

That joke came to my mind when I read three short tributes to biologist E.O. Wilson in Skeptical Inquirer (May/June 2022). Wilson passed away on December 26, 2021, at age ninety-two. The tributes are by evolutionary biologist and science popularizer Richard Dawkins, evolutionary developmental biologist Sean B. Carroll, and cognitive linguist Steven Pinker. Predictably, all three portraits are very positive. Just as predictably, they are somewhat flawed.

Let me first acknowledge where I agree with Dawkins, Carroll, and Pinker. Wilson, whom I’ve met a few times during my career as an evolutionary biologist first…

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Plato’s mistake

Massimo Pigliucci

by Massimo Pigliucci

What is your take on metaphysics? Mine isnot particularly positive. At least, I am deeply suspicious, and largely reject, the whole approach to the field known as “analytic” metaphysics, which has been dominant since the beginning of the 20th century. (I am increasingly skeptical of the value of all analytic philosophy, but that’s a story for another time. And no, I’m no friend of the continental tradition either!)

My favorite whipping boy is a leading analytic metaphysician, David Chalmers, who initially became famous for his notions about consciousness and philosophical zombies, and has more recently embraced equally problematic notions like panpsychism. Chalmers and his colleagues proposed their “theories” on the basis of their intuitions and of what they find “conceivable,” regardless of whether there is any empirical evidence for their speculation. Indeed, they tend to be contemptuous of empirical evidence, dismissing it as…

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Introductions to the Aeneid – 3. David West

Books & Boots

I own three English translations of the Aeneid:

  • the 1956 Penguin classics prose translation by W.F. Jackson Knight
  • the 1970 verse translation by Allen Mandelbaum
  • the 1991 Penguin classics prose translation by David West

This is the last of three blog posts giving detailed analyses of the introductions to each of these translations. This one looks at David West’s introduction to his 1991 translation. It also gives examples of each of the translators’ work, first their renderings of the Aeneid’s opening 12 lines, then of the final few lines.

1991 Penguin classics prose translation by David West

Unlike the vapouring spiritualist Jackson Knight, and the namedropping Vietnam War protestor Mandelbaum, West is wonderfully unpretentious and to the point. In his introduction’s brisk 6 pages he bluntly says the Aeneid is about a man who lived 3,000 years ago in Asia Minor so – why should we care?

1. The origins…

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Human accident fallacy

Some years ago, when I was working as a regulatory consultant to VicRoads, they asked me to use the term “road crash” rather than “road accident”. They pointed out that an accident is defined as an unintended event not directly caused by humans.

Vehicle collisions are not usually accidents; they are mostly caused by preventable behaviours such as drunk or careless driving, or intentionally driving too fast. Vehicle collisions invariably have a human cause, so the use of the term “accident” is misleading in this context.

The use of the word accident to describe car crashes was promoted by the US National Automobile Chamber of Commerce in the middle of the 20th century, as a way to make vehicle-related deaths and injuries seem like an unavoidable matter of fate, rather than a problem that could be addressed. The automobile industry accomplished this by writing customised articles as a free service for newspapers that used the industry’s preferred language. These articles were deliberately fallacious.

For this reason, the US National Highway Traffic Safety Administration has since 1994 asked media and the public not to use the word accident to describe vehicle collisions.  Similarly, the Australian National Road Safety Strategy 2021–30, endorsed by the responsible Federal and State Ministers, uses the term “road crash” rather than “road accident”. More widely, health and safety professionals generally prefer using the term “incident” in place of the term “accident”.

Confusingly, the common current meaning of the English word “accident” has almost nothing to do with Aristotle’s philosophical concept of the “fallacy of accident”, which was one of the thirteen fallacies that Aristotle discussed in his book On Sophistical Refutations. Aristotle’s accident fallacy is difficult to explain here, but doesn’t have anything to do with car crashes or people slipping on banana peels.

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Of Friendship by Francis Bacon

Books & Boots

Bacon is a hugely enjoyable read and his pithy brevity is a welcome break from Cicero’s rambling verbosity.

Francis Bacon

Francis Bacon was born in 1561 into an eminent family. His uncle was the Lord Cecil who became the first minister to Queen Elizabeth. Like Cicero he made a career at the bar and in politics, sitting as MP for various constituencies. He was helped up the ladder by the Earl of Essex so when the latter rebelled against Elizabeth in 1601, Bacon’s zealous prosecution of his former patron aroused much bad feeling.

When the old queen died and was replaced by James VI in 1603 Bacon’s ascent up what Disraeli called the slippery pole continued. He was knighted, became clerk of the Star Chamber, Attorney General, Privy Counsellor and Lord Keeper of the Seal, finally becoming Lord Chancellor.

It was at the height of his success, in 1621, that…

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Selected quotes from  Quit Smoking Weapons of Mass Distraction

Simon Chapman AO

My new book  Quit Smoking Weapons of Mass Distraction (Sydney University Press 2022 359pp ISBN 9781743328538) will be published as an e-book on June 26 and as a paperback on July 1, 2020

You can read the Introductory chapter free here

You can order the book at Amazon here ($AUD4.99 e-book; $AUD28.80 paperback)

Below are quotes from the book that I hope will stimulate your interest.

The core message of the book

“The core message throughout this book has been that the overwhelming dominance of assisted cessation in the way that quitting has been framed over the past three decades has done a huge disservice to public understanding of how most smokers quit. Around the world, many hundreds of millions of smokers have stopped without professional or pharmacological help.”

On the dominance of unassisted cessation in how most ex-smokers quit

“If we were able to estimate the total number of…

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Can does not imply ought

‘Ought implies can’ is an ethical principle ascribed to the 18th century philosopher Immanuel Kant which claims that if a person is morally obliged to perform a certain action, then logically that person must be able to perform it. It makes no sense to say that somebody ought to do something that it is impossible for them to do. As a corollary, a person cannot be held responsible for something outside their control.

On the other hand, the converse relationship ‘Can implies ought’ does not apply. Just because a person can do something, it does not logically follow that they ought to do it.

When the Australian Governor-General Sir John Kerr dismissed the Whitlam Government in 1975, a common argument in favour was that he had the power to do it. However, this was an irrelevant red herring – hardly anybody disputed the power of the Governor-General to dismiss the Prime Minister. What they did dispute was whether he ought to have done it.

To give another example, in most cases it is lawful to tell lies, and it is often possible to get away with lying. But that does not mean that lying is acceptable behaviour (except for ‘white lies’ to avoid hurting somebody’s feelings or to otherwise minimise harm).  

In terms of logic, this reverse relationship is a logical fallacy known as ‘Affirming the consequent’ (sometimes called the fallacy of the converse) which consists of invalidly inferring the converse from the original statement. This fallacy takes the following form:

Premise 1: If P, then Q.

Premise 2: Q.

Conclusion: Therefore, P. 

Applying this form to the current case:

Premise 1: If you ought to do something, then you can do it.

Premise 2: You can do it.

Conclusion: Therefore, you ought to do it.

I realise that this is not a very common fallacy, and pointing it out might just seem like common sense, but it does have relevance for critical thinking and logical argument.

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‘Jelly Roll Morton Concert’

By Tim Harding

On the evening of 3 April 2014, The Red Hot Rhythmakers presented a sold-out ‘Jelly Roll Morton Concert’ at the Flying Saucer Club in Elsternwick, a suburb of Melbourne.  Billed as ‘a musical journey through the life of pianist, composer and bandleader Jelly Roll Morton’, the concert traced Morton’s jazz career from the bordellos of New Orleans to the height of his fame in Chicago and New York.

Born Ferdinand Joseph LaMothe in 1890, Jelly Roll Morton began his career in the early twentieth century as a pianist in the New Orleans ‘red light district’ (DeVeaux and Giddens 2009, 78-79, 92-93).  Regarded as the first great jazz composer, in that he combined predetermined elements with improvisation (Dapogny 1982, 5), Morton composed an impressive number of works.  Now considered to be staples of the early jazz repertoire (Schuller 1968, 135); many of these compositions featured in this concert. 

On this occasion, American cornet player Andy Schumm and drummer Josh Duffee joined the nine-piece Melbourne jazz band The Red Hot Rhythmakers.  Led by the talented young saxophonist and arranger Michael McQuaid, The Red Hot Rhythmakers specialise in performing authentic big band jazz and hot dance music from the 1920s.  By transcribing original recordings, McQuaid also arranges many of the works in the band’s repertoire, often including the horn solos.  He also provided an interesting commentary on Morton’s life and works throughout the concert. 

Figure 1 – The Red Hot Rhythmakers at the Flying Saucer Club with Andy Schumm on cornet (Michael McQuaid is third from left) (photograph by the author).

The full band comprised six horns (three brass and three reeds) seated across the front of the stage, with a three-piece rhythm section of banjo/guitar, drums and string bass/sousaphone positioned behind.  A notable absence was a piano, especially in view of Morton’s prominence as a leading early jazz pianist.  In light of this, the rhythm section sounded a little thin when compared to the lush horns, especially in two-beat passages where piano chords would have helped to emphasise the off-beats (beats 2 and 4 in each bar).

In order to showcase the full band, the evening commenced with a rousing up-tempo rendition of Morton’s composition ‘Burnin’ the Iceberg’.  This work has two strains – a fast 12-bar blues followed by a 16-bar chorus with instrumental breaks.  After a subdued clarinet solo by McQuaid, Schumm responded with a blaring hot cornet solo in the style of Morton’s original 1929 recording, followed by the full band playing harmonised riffs behind improvised clarinet in the final choruses. 

Following this opening number, and in order to provide a contrast, the group played Morton’s ‘Black Bottom Stomp’, a two-part work separated by a 4-bar key modulation from Bb to Eb, with three different themes or variations in the 16-bar first part (Dapogny 1982, 201-209).  On this occasion, the band played this fast-tempo piece with only 3 horns (cornet, clarinet and trombone).  This combo allowed room for more collective improvisation during the ensemble passages than would have been possible with the full band. McQuaid played a rhythmic clarinet solo in the lower register and Schumm shone with an exciting stop-time cornet solo, placing his hand half over the bell to provide tone colour in the 1920s Chicago jazz style.

Interestingly, most of Morton’s compositions were not of the usual 32-bar AABA Tin Pan Alley form.  They were original structures, often comprising multiple strains of different lengths (such as 16 bar verses and 32 bar ABAC choruses), like the ragtime tunes and brass band marches that Morton grew up with (Schuller 1968, 135).  

The full band then played two of Morton’s medium-tempo works based on the 12-bar blues, ‘London Café Blues’ and ‘Dead Man Blues’.  The latter piece began with a somber funeral dirge presaging the blues, but both works contained melodic variations so innovative that the average listener may not have recognised them as blues. 

The regular drummer with the band, Sandra Talty, is also a fine jazz singer influenced by Mildred Bailey and Billie Holiday.  Sandra also took to the stage to sing the Morton compositions ‘Sweet Substitute’, ‘Doctor Jazz’, ‘Good Old New York’ and ‘Why?’, accompanied by a smaller combo.  Unusually, the wistful ballad ‘Sweet Substitute’ (which is about an illicit sexual relationship) consisted of a verse and chorus of 16-bars each, whereas the medium tempo ‘Doctor Jazz’ had a more traditional 16-bar verse and a 32-bar ABAC chorus.  The string bassist Leigh Barker played arco (using the bow) in ‘Sweet Substitute’ to great effect.  

One of Morton’s most famous compositions performed towards the end of the concert was ‘King Porter Stomp’, which has three different strains of 16-bars each.  The full band played it in the late 1930s swing band style of Benny Goodman, for whom it became a huge hit during the Big Band Era.  The full band finished the concert with a very fast version of the jazz standard ‘Panama’ (composed by William Tyers rather than Morton).  This tune featured some outstandingly rapid fingering by the three saxophones playing in harmony, resulting in enthusiastic applause from the audience. 

Overall, the concert was a fine tribute to jazz’s earliest composer, authentically played by some of the best young musicians in this genre.

References

Dapogny, James. 1982. Ferdinand “Jelly Roll” Morton: The Collected Piano Music.  Washington D.C: Smithsonian Institution Press.

DeVeaux, Scott and Giddins, Gary. 2009. Jazz. New York: W.W. Norton & Company.

Schuller, Gunther. 1968. Early Jazz – Its Roots and Musical Development.  New York: Oxford University Press.

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Special Pleading

Special pleading is a form of inconsistency in which the reasoner doesn’t apply his or her principles consistently. It is the fallacy of applying a general principle to various situations but not applying it to a special situation that interests the arguer even though the general principle properly applies to that special situation, too.

Example:

Everyone has a duty to help the police do their job, no matter who the suspect is. That is why we must support investigations into corruption in the police department. No person is above the law. Of course, if the police come knocking on my door to ask about my neighbors and the robberies in our building, I know nothing. I’m not about to rat on anybody.

In our example, the principle of helping the police is applied to investigations of police officers but not to one’s neighbors.

Source: The Internet Encyclopedia of Philosophy

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Prehistoric timelines

Texts about prehistory are liable to use three different timelines or naming systems interchangeably so it’s as well to be absolutely clear about …

Prehistoric timelines

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