Lecture 2, scientific reasoning and praxis.pptx

7/27/2019 Lecture 2, scientific reasoning and praxis.pptx

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Studium Generale

Section for linguistics students

Lecture 2: Scientific reasoning and praxis 1


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Contents

Examination again

The rescheduled class

Todays topics

Pseudo-science and hoaxes

The philosophy of science

Scientific reasoning

Deduction

Induction

Inference to best explanation

Explanation

Causality

Conclusion2


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Examination

Confirming ...

3 questions each relating to both parts of the

course

From which you select 1

Essays are 10 pages

3


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The rescheduled class

We agreed last time to the following changes:

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Lecture Date Topic Readings

1 8 March What is science, what is a scientific

approach?

Okasha 2002, Chapter 1; Principe

2011, Chapters 1-2

2 15 March Scientific reasoning and praxis Okasha 2002, Chapters 2-3; ;

Dixon 2008, Chapter 2

3 22 March History of the science of language Campbell 2001; Robins 1984

4 29 March Linguistics as a science: linguistic

theories and praxis

Sampson 1980; Butler 2003,

Chapters 1-2

5 10 April The culture of science Okasha 2002, Chapter 5; Dixon

2008, Chapters 4-5

6 12 April Science in culture Okasha 2002, Chapter 7; Oaks2001

This class will be in 1467-515

Tirsdag den 10.04.2012 fra kl.

9 til kl. 12


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Pseudo-science and hoaxes

An influential philosopher of science, Karl Popper wasconcerned in distinguishing science from pseudo-science

He suggested that a central feature of a scientific theory isthat it be falsifiable

That it makes predictions that can be tested against experience

That is, there are observations that could count against the theory

The theory is not compatible with every possible state of the world

Otherwise, if the theory is consistent with outcome, it cant be tested,and is pseudo-science

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One of his favourite whipping-horses was Freudspsychoanalysis

Popper argued that the theory could be reconciled with any

empirical finding

Whatever the behaviour of the patient, an explanation could be foundin terms of the theory

Nothing could show it is wrong

One of Poppers examples:

A man pushes a child into a river, intending to drown him

Another man dies trying to save the child

Freudian theory accounts for both behaviours equally easily

The first was repressed

The second had achieved sublimation

According to Popper concepts like repression and sublimation could

permit compatibility with any data the theory is unfalsifiable 6


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Popper argued that by contrast Einsteinstheory of gravitation makes very definitepredictions

These can be tested against observations

Arthur Eddington organised an expedition to the island ofPrncipe near Africa to observe the Solar eclipse of 29 May

1919 that provided one of the earliest confirmations ofrelativity

During the eclipse, he took pictures of the stars in the regionaround the Sun

According to the theory of general relativity, stars with light

rays that passed near the Sun would appear to have beenslightly shifted because their light had been curved by itsgravitational field.

This effect is noticeable only during eclipses, since otherwisethe Suns brightness obscures the affected stars.

Eddington showed that Newtonian gravitation could be

interpreted to predict half the shift predicted by Einstein 7


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Poppers ideas sound plausible

There is something wrong with a theory if it can be madeto fit any observational data

But there is a bit more to the story than this

There are other differences between Freuds theory and Einsteins

In particular controllability of context which is after all highly relevant

The social sciences have the problem that many variables are simplynot subject to experimental control

And sometimes if they are the unnaturalness makes the

findings less plausible and significant

Critiques of psycholinguistics and neurolinguistics aresometimes based on the apparent decontextualisedexperimental circumstances

This can result in difficulties in falsification of the theories 8


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Scientists frequently find empirical facts that dontexactly fit with the predictions of a theory

But rather than reject the theory, they attempt to save it

by postulating some other factor that needs to be takeninto account

In the case of Galileos falling objects experiment, if a lead balloonand a feather were dropped at the same time, they would not

reach the ground at the same time

Instead of rejecting his theory, he takes air resistance into account

A more complex case observations of the orbit of Uranusshowed some differences from the predictions of Newtonian

physics

Independently in 1846 Adams and Leverrier suggested the existence ofanother planet that provided the gravitational force that would beresponsible for the irregularity in the orbit of Uranus

This planet (Neptune) was subsequently discovered almost exactly wherepredicted

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This is reminiscent of Saussures

postulation of proto-Indo-European

laryngeals to account for certain

otherwise inexplicable facts about

Greek morphology.

Subsequently vindicated by Hittite.

Note the obvious parallel to

Poppers critique of Freud:

By taking air resistance intoaccount we could explain

almost any empirical finding


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Especially in the case of social sciencesincluding linguistics theories are not alwayseasily falsifiable in practice

Even in physics falsifiability may be beyond presentmeans of measurement

I believe this is the case for string theory

It is an important part of the scientific endeavourto account for conflicts exceptional facts while

retaining the theory, and working within it

More on this later

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Linguists do on occasion critique one another on the

basis of the unfalsifiablity of the others claims.

Generally speaking I dont hold this critique in high

regard:

Extreme difficulties in applying this notion to the

linguistic sign

It is the less interesting claims that are more easilyfalsified claims not mediated by the sign

Compare two approaches to givennessGivns and

mine


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Popper attempted to characterise science in aPlatonic way in terms of an essential featurethat must be possessed

His approach to this task seems eminently reasonable:

Compare instances of pseudo-science with good science,and identify the differences

The point is he may have selected the wrong differences

Another possibility is that there is no such essentialfeature defining science

Like games according to Wittgenstein, there are looseclusters of features characterising things we call games, butno Platonic essence

Games show family resemblances to one another 11


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Of a rather different nature to pseudo-scienceare hoaxes and forgeries in science

Consideration of these may give us some inklingsinto the nature of science itself (when properly

done)

Remember my adage that it is when things go wrong

that we learn most about how things work rightly

This is implicit in what Popper attempted12

Hoaxes and forgeries


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One of the most famous hoaxes in the history ofscience was the Piltdown Man:

Bone fragments were presented as the fossilised remainsof a previously unknown early human.

Parts of a skull and jawbone, said to have been collected in 1912from a gravel pit at Piltdown, East Sussex, England

The Latin name Eoanthropus dawsoni("Dawson's dawn-man", after the collector Charles Dawson) was given to thespecimen

The significance of the specimen remained the subject ofcontroversy until it was exposed in 1953 as a forgery

The lower jawbone of an orangutan that had been deliberatelycombined with the skull of a fully developed modern human

Why? What was the point of this forgery?

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Scientific frauds and forgeries are not all that

infrequent

Recent examples:

Milena Penkowa (born 1973) is a Danish neuroscientist

who was a Professor at the Panum Institute at the

University of Copenhagen from 20092010

Her prolific research mainly concerned the protein

metallothionein

She received the Danish Elite Research prize in 2009. In 2010

she was accused of scientific misconduct and resigned her

professorship

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Marc D. Hauser (born 25 October 1959) is an Americanevolutionary biologist and a researcher in primate behaviorand animal cognition who taught in the PsychologyDepartment at Harvard University.

In August 2010, a committee of Harvard faculty found Hausersolely responsible for eight counts of unspecified scientificmisconduct.

On August 1, 2011 Hauser resigned his position at Harvard

Hwang Woo-suk (Korean:, born January 29, 1953) isa South Korean veterinarian and researcher, professor oftheriogenology and biotechnology at Seoul NationalUniversity (dismissed on March 20, 2006)

Became infamous for fabricating a series of experiments, whichappeared in high-profile journals, in the field of stem cell research

Until November 2005, he was considered one of the pioneeringexperts in the field, best known for two articles published in the

journal Science in 2004 and 2005 where he reported to have

succeeded in creating human embryonic stem cells by cloning. 15

I h i li i i


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It happens in linguistics too

Lanyon-Orgill (19242002) for a full story see Ross

Clark (2011). On the margins of Pacific linguistics: P.A.Lanyon-Orgill. Language & History54(2): 164-177.

In the midtwentieth century his name was quite well knownamong Pacific-area linguists, through a combination ofderivative publication with fictive enhancement both of hisown scholarly persona (degrees he never got, colleagueswho dont exist) and of the data he presented

Changes to his reputation following the exposure in the1980s of his falsification of alleged eighteenth-century

manuscripts, and the realization that fraudulent elementswere present in his work from the very beginning.

Nevertheless, some of his work (particularly a few dictionaries)has been found by experience to be sound

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C f f i t i i l d


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Consequences of forgeries to science include:

Waste of resources

Misdirection of research

For example, the Piltdown Man fraud:

The significance of the bona-fide fossils being found was mutedfor decades because they disagreed with Piltdown Man and thenotions that the faked fossils supported.

The paleontologist Arthur Smith Woodward spent time atPiltdown each year until he died trying to find more PiltdownMan remains.

The misdirection of resources kept others from taking the realfossils more seriously and delayed the reaching of a correct

understanding of human evolution.

The Taung Child, which should have been the death knell forthe view that the human brain evolved first, was insteadtreated very critically because of its disagreement with thePiltdown Man evidence.

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In the case of Lanyon-Orgill, I quote from Clarks article

Unexpected evidence of the potential of this material togenerate ideas even beyond linguistics appeared in 2003, ayear after Lanyon-Orgills death, and more than 20 yearsafter Geraghtys review. Australian journalist and historianKeith Vincent Smith, studying early contacts betweenEuropeans and Aborigines in the Sydney area, came uponLanyon-Orgillsbook with its three Lanyon manuscript

wordlists from Botany Bay. Whereas the narratives ofCooks first voyage state that the Aborigines werestandoffish, if not actually hostile, and that close contactproved impossible, here was evidence that three crewmembers in three different places had in fact sat downwith the indigenous people and learned something of theirlanguage.

This fed into an ongoing debate in Australia about thehistory of EuropeanAboriginal relations, so that both theUniversitys publicity apparatus and the magazine AQpicked it up (Jopson 2003; Smith 2003, 2004).

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Ho does science g ard against forger and


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How does science guard against forgery, anddetect it?

Results not replicable by other investigators

Results look too good to be true

Error analysis:

Measurements generally have a small amount of error, andrepeated measurements of the same item will generally result inslight differences in readings.

These differences can be analyzed, and follow certain knownmathematical and statistical properties.

If a set of data appears to be too faithful to the hypothesis, i.e.,

the amount of error that would normally be in suchmeasurements does not appear, a conclusion can be drawn thatthe data may have been forged.

Error analysis alone is typically not sufficient to prove that datahave been falsified, but it may provide the supporting evidencenecessary to confirm suspicions of misconduct

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In the case of Lanyon-Orgill the main give-aways were:

Problems with the dates of manuscripts:

one wonders, for example, how an English

translation of Humboldts TahitianEnglish vocabulary,dated 1845 (130) could have been inserted into a

volume bound in 18101815 (286), and whether theJohn Lanyon who catalogued the manuscript is thesame as the John Lanyon (183271) who was eaten by

a crocodile.

References to people and articles so obscure asnot to exist!

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Captain Cooks South Sea Island Vocabularies whichcontained, among other things:

Vocabularies from languages spoken in places where Cooknever landed

Wordlists that must have been gathered duringcircumstances of conflict with indigenes

Error analysis:

The canonical vocabularies showed the normal quota of errorsand inexplicable forms to be expected in such early lists,somewhat enhanced by Lanyon-Orgills ineptitude at identifyingmodern equivalents for the words. With the Lanyon vocabularies,by contrast, he scored 100 percent, and the resemblances

between manuscript and modern language were uncannilyclose. The apparently inescapable conclusion was that the Lanyonlists were created not by contemporaries of Cook, but on thebasis of later sources by a modern hand, using a linguisticequivalent of the distressing applied by makers of fake antiques(for example English-based spellings such as ee, oo would be

substituted for modern i, u). 21


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More on frauds and forgeries later ...

For now we can just bear in mind the seriousness

of vested interests drug companies, tobacco

companies, and so forth

The possibility that research funded by non-

governmental commercial interests will be controlled

by these interests

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The philosophy of science

This field of study is concerned with the familyresemblances amongst the fields called sciences,

With identifying and analysing the methods ofenquiry of the sciences

It is concerned with the assumptions implicit inscientific practice

Things that scientists presume but do not discuss or critique

Doing science of course is impossible without makingassumptions, and many of them are invisible to the people usingthem

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An example: scientific experimentation

A scientist does an experiment, getting a certainresult

She repeats it a few times and gets the same

result

After a few goes, she will probably stop, believing

that on further repetition given the same

conditions of performance the same result will

arise

Sounds like a plausible presumption

But why? How do we know that this will happen?

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Wearing your scientists hat, these questionsdont really concern you

But many scientists also doff their scientific hats, andthink about these questions

Many prominent scientists like Descartes, Newton, Einstein

thought about such questions, e.g.

How science should be carried out

How much confidence to place in its methods

Whether there are limits to scientific knowledge and praxis

The increasing specialisation of science has resulted in lessinterest in the philosophical questions by scientists

And also the polarisation of science and humanities (where

philosophy belongs) of the modern university system 25


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Scientific reasoning

We now discuss and evaluate some processesemployed or claimed to be employed in

scientific reasoning

Deduction

Induction

Inferences of best explanation

Explanation

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Deduction

This method of reasoning everyone accepts asvalid

Study of deductive reasoning is a part of logic

An example of this type of reasoning is modusponendo ponens:

A. All men are mortalB. Socrates is a man

C. Socrates is mortal

Linguistic examples? 27


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A. All languages have vowels and consonants

B. Nyulnyul is a language

C. Nyulnyul has vowels and consonants

A. All languages have nouns

B. Shua is a language

C. Shua has nouns

This principle tells us that if the premises aretrue, so is the conclusion

The reasoning is valid and exciting eh? But the premises need not necessarily be

E.g. Not all languages have nouns (as a distinct part of

speech) 28


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What about the following deductions?

A. Most languages have vowels and consonants

B. Nyulnyul is a languageC. Nyulnyul has vowels and consonants

A. All languages have vowels and consonants

B. Ngank is not a language

C. Ngank has neither vowels nor consonants

A. It is not the case that all languages have vowels andconsonants

B. Some languages have neither vowels nor consonants

A. It is not the case that all languages have vowels andconsonants

B. Some languages have either no vowels or no

consonants 29


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Induction

Many people have suggested a naive inductivist

account of science

That places induction as the central method of scientificreasoning

Basis of naive inductivist story

Science starts with observations, using their unimpairedsense organs (ears, eyes, nose) possibly augmented with

measuring devices These observations are recorded accurately and faithfully,

without prejudice

Statements about some aspect of the world areestablished and justified directly via the observers use of

their senses 30

Examples of observational statements of course, some


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Examples of observational statements of course, someinterpretative knowledge beyond simple observation isessential: these are not completely atheoretical statements

Gooniyandi is spoken in the town of Fitzroy Crossing

Shua has a click sound in the word kick

The last fluent speaker of Unggumi died in the last decade ofthe twentieth century

In principle, these statements can or could be established byobservation the third one, with some qualifications:

It was observable at some point in time

These are singular statements; in science we are concerned

not with singular statements, but with makinggeneralisations

With statements that are universal in application:

Statements that apply to all phenomena of a particular kind 31

H d f h i l


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How do we get from the singular statementsto the universal ones?

One answer is by induction

From a set of singular statements we can legitimatelygeneralise a universal law, provided certain conditionsare met

An example:

We make a set of observational statements aboutGooniyandi words, that all are made up of vowels andconsonants

We generalise from the set of observations to the lawthat all words in Gooniyandi consist of both vowels andconsonants

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Wh t th diti th t t b t?


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What are the conditions that must be met?

The number of observational statements must be

large The observations must be repeated under a variety of

conditions

No observational statement should conflict with the

universal law

In our Gooniyandi example this means we would need to:

Examine many different words We should observe them not just in citation, but also in use in

different sentences

If we observed an exception, then the law would not beuniversally viable

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The naive inductivist view of science is that


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The naive inductivist view of science is thatscience is based on the principle of induction:

If a large number of Xs have been observed in a widerange of conditions, and if all these Xs withoutexception possess the property Y, then all Xs have theproperty Y

Basically the view is that science proceeds asfollows:

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Facts acquired

through

observation

Laws and

theories

Predictions and

explanations

Th bl i h h i i l f


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There are problems with the principle ofinduction

Bertrand Russells inductivist turkey:

This turkey found that, on his first morning at the turkeyfarm, he was fed at 9 a.m. However, being a good inductivist,he did not jump to conclusions. He waited until he had

collected a large number of observations of the fact that hewas fed at 9 a.m., and he made these observations under awide variety of circumstances, on Wednesdays andThursdays, on warm days and cold days, on rainy days anddry days. Each day, he added another observation statementto his list. Finally, his inductivist conscience was satisfied and

he carried out an inductive inference to conclude, "I amalways fed at 9 a.m.". Alas, this conclusion was shown to befalse in no uncertain manner when, on Christmas eve,instead of being fed, he had his throat cut. An inductiveinference with true premises has led to a false conclusion.(Chalmers, p. 14)

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Linguistic example

We observe through collection of many instancesof Agent NPs in Gooniyandi, in a range of differenttransitive clauses, with many different types of NP(pronominal, animate, inanimate, ...) each ofwhich is marked byngga

We conclude that all Agent NPs are marked by themorphemengga

Seems reasonable But how certain can we be of our conclusion

Can we be any more certain than Russells turkey?

Not really36


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In fact, once we stop observing elicited

examples and look at narratives and everyday

speech we find that there are exceptions

Agent NPs that are not marked by this morpheme

A difficulty is that what counts as a broad range of

circumstances is not clear

Our elicitation aimed at gathering a broad range of data But in fact it was broad in the wrong ways

There is no way we can determine what the relevant

range of circumstances is

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h d i


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Some have suggested a way out is tointroduce probabilities into the story

That the inductive inferences be evaluated interms of probabilities

E.g. the likelihood that the our general statement isvalid given the set of specific statements

Possibly this might sound like a reasonable solution

Intuitively it is reasonable to expect that with increasing

numbers of singular statements the probability will increase

But the turkey example shows that this is not always valid

And how could one calculate the probability?38


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Intuitively, if we have a good explanation the

probability of the universal statement is

increased

But to include this involves a problem for the

nave inductivist story of the scientific process

It cant be a simple unidirectional process

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Another difficulty with the proposals concerns

the singular statements conflicting with the

generalisations

In our Gooniyandi word structure example, we will

eventually find words like mm, aa, mhm

But the obvious thing to do is not to immediately throw

out the generalisation

Rather, we look at refining the notion of word

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Philosophers of science do not generally

regard the nave inductivist story as a

plausible model of the scientific process

Or consider induction to have a central place in

scientific reasoning

This is not to say that it has no place at all:

Presumably we use something like induction in everyday life

From observations we construct expectations as to what

will happen a matter of survival

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Exercise for next time:

What is mathematical induction?

How if at all is it like scientific induction?

How do mathematicians and philosophers of

mathematics regard it?

Are they as cautious and critical of it as in science?

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Inference to best explanation

Another type of non-deductive reasoning, where

from a set of specific statements a generalstatement is inferred that explains them

For example:

There are close anatomical similarities between thelegs of horses and zebras

horses and zebras descend from a commonancestor animal

This provides an explanation of the similarity

It is better than the alternative that god created both speciesseparately if so, why the similarity: an omnipotent beingcould have employed completely different templates for the

legs 43

A similar linguistic example:


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A similar linguistic example:

Italian and Spanish share a lot of similarities in

their lexicons

The definite and indefinite articles of Italian andSpanish are very similar in form and system(distinguishing two genders)

Italian and Spanish both derive historically fromthe same ancestor language

This explanation provides a better account of the factsthan that the words and articles in the two languagesare just accidentally similar

We know from Saussure that the linguistic sign is arbitrary

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Cl l h i d l i ll il


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Clearly the premise does not logically entail

the conclusion in these cases

There are other possibilities, also consistentwith the facts:

Although not a good explanation, there is a tinychance that the similarities are a result of chance

They might alternatively be the result of

borrowing between the two languages

How can we decide which is the best

explanation?45

We add in further observations (specific statements) or


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We add in further observations (specific statements) orgeneralisations

Add to the list of similarities til we find that the amount ofborrowing would have been so large it is an implausiblestory

Observe that it is much less common for languages toborrow core vocabulary and grammatical morphemes than

other lexemes

Since the similarities are in these domains as well as in non-corevocabulary, this explanation is not as good

Observe that among the similarities in the lexicon thereare a number of recurrent sound correspondences

Common origin together with regular sound change provides a

better explanation than borrowing 46

This example illustrates the development of


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This example illustrates the development of

the comparative method in C19

Numerous linguists contributed to its shaping

Rask, Grimm, Grassman, Saussure

They observed the similarities in modern

languages, and attempted to identify theconditions under which retention and borrowing

and other explanations provide the best

explanations of similarities

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This method of reasoning is common in linguistics


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This method of reasoning is common in linguistics

Another example comes from my own descriptive workon Gooniyandi

Here is a potted version of the story of the analysis ofthe pronoun system in the language

I observed early on that there were two 1st person non-singular pronominals, ngidiand yaadi

I concluded that the language made a distinction betweeninclusive and exclusive

Which is widespread in Australian languages

Specifically,

Ngidiwould be 1exclusive, dual or plural

Yaadiwould be 1 inclusive, dual or plural

Alan Rumsey drew exactly the same conclusion for Bunubawhen he did his first fieldwork a couple of years earlier

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These are not the only possibilities but we were


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y pcontent with them

For a while anyway

Within a few weeks of fieldwork however I found thatpeople were just not using the 1st person pronouns as theyshould be if it was an inclusive-exclusive system

Observations conflicted with expectations

Ngidiwas used for not just 1&3 but also 1&2

Yaadiwas never used for 1&2, only for 1&2&3

The observations were followed up with experiments i.e.getting speakers interpretations of invented forms:

I asked speakers what does yaadi-yoorroo mean?

Some rejected the form

Some said it means we three! 49

I of course told Alan Rumsey (my supervisor then)


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I of course told Alan Rumsey (my supervisor then)about this problem

New to him, so he also tested things out in Bunuba

Finding exactly the same situation as in Gooniyandi

So we ended up with a set of specific statements

Ngidimeans

1&2

1&3

1&3&3

Yaadimeans

1&2&3

1&2&3 50

Neither of us was happy with these specific


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Neither of us was happy with these specificobservational statements

We wanted to infer a system to suggest ageneral statement that would account for them

My first attempt was to suggest a contrast betweenrestricted and unrestricted and this appeared in mygrammar (1990)

Basically 1 restricted would be a category that included 1 and

another person category, but just one 1 unrestricted would include all person categories

However, I was never satisfied with this explanation itdoes not sound nice!

51

In early 1990s Mark Durie suggested an alternative


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In early 1990s Mark Durie suggested an alternative

We were wrong looking for an explanation:

Really, the system was an inclusive-exclusive one, in which therehappened to be accidental homophony between:

1dual exclusive ngidi(-yoorroo) and

1dual inclusive ngidi(-yoorroo)

This saves our explanation

The problem was that not only was there accidental homophonyin these pronominal forms, but also in:

The oblique forms (ngirrangi) And throughout the verbal paradigm (jirr-)

My conclusion this is too systematic to be accidental:there must be an explanation

52

In the mid 1990s Rumsey and myself both


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In the mid 1990s Rumsey and myself both

suggested explanations

Mine was:

The system is an inclusive-exclusive one, but it

operates on different principles than the standard

one

What is included or excluded is not the hearer

It is hearers specifically the hearer plus others

Ngidiexcludes hearer plus others

Yaadiincludes hearer plus others 53

Just apply logic to

Not (hearer & other(s))

And you get the right

results

In my view this is the best explanation


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y p

A long road to its discovery, but preferred over the accidentalhomophony story

And provides a neater account than what Rumsey suggested at thesame time

Which was not intuitively satisfying

We do this regularly in descriptive linguistics

Observe something and immediately seek an explanation tounderstand it

I hear an intransitive subject NP marked in Pri marked by amorpheme

I conclude immediately (tentatively) that the language is ergative

Because in accusative languages the accusative is usually marked, thenominative unmarked

Of course, then the conclusion is immediately tested 54

E l ti


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Explanations

One of the most important aims of science is to

explain the world

Astronomers aim to explain why solar eclipses occur

when they do

Linguists aim to explain e.g.:

Why languages have the structures they do

Why and how some languages are similar to one another

How languages are used in speech

Why a bilingual person choses to use one language rather

than another in a given context55

What is an explanation?


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What is an explanation?

Carl Hempel (1905-1997) suggested the

covering law model for scientificexplanation in 1950s

While a student in Gttingen he encounteredDavid Hilbert and was impressed by his attempt to

base all of mathematics on solid logical

foundations derived from a limited number of

axioms (Hilbert's Program)

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Hempel suggested that scientific explanations
http://en.wikipedia.org/wiki/File:Hilbert.jpghttp://en.wikipedia.org/wiki/File:Hilbert.jpg


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Hempel suggested that scientific explanationshave logical structure of arguments

Premises followed by conclusions (what needs to beexplained)

To explain why the ergative marker in Gooniyandi issometimes used and sometimes not used one needs

to set up a set of premises from which this conclusionderives

Accounting for the uses and non-uses

What are the characteristics of a viable scientificexplanation?

How should the premises and conclusions be related? 57

Hempels suggestion:


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p gg

The premises should entail the conclusion (logically a

deductive argument) The premises should be true

The premises should comprise at least one generaluniversal statement at least one general law

Schematically:

General lawsParticular facts

Phenomenon to be explained

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A linguistic example:


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A linguistic example:

We want an explanation for why a bilingual

speaker in the Austrian village Oberwart switched

from Hungarian to German in an argument

In the following discourse a mother is collecting

her daughter, who has been looked after by thegrandparents during the day.

The girl has been misbehaving, and the

grandfather sympathises with her.

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The switch to German justifies thechoice of child-rearing methods. This

switch to German ends the argument

between the mother and grandfather

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How might an explanation go according to


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How might an explanation go according toHempel?

Languages express speakers personal and ethnicidentities

Hungarian expresses speakers ethnic identity as member of

a small village in Austria German expresses speakers identity as an Austrian

Choice of language in bilingual situation indicates

choice of identity

I am an Oberwartian we are intimates

I am an Austrian we are not intimates

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We have there general laws (concerning


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We have there general laws (concerning

language affiliations and choice) and particular

facts (about the language use in the community)

We conclude that the switch to German in the

conversation was motivated by the speaker wishing to

distance herselffrom her interlocutor

She establishes herself as an Austrian, not an Oberwartian

Austrian is dominant, the language of the powerful

By implication she is the powerful one with the powerfulargument

So we can account for the effect of her language choice for

her successfully winning the argument over her father

62

Similarly for the other linguistic example


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Similarly for the other linguistic example,

optional ergative case marking in Gooniyandi

though with some twists

A general statement I have proposed in recent

work is given that a grammatical morpheme is

optional:

Usage vs. non-usage always codes meaning relating to

the interpersonal dimension

Specifically, this relates to the general dimension ofjoint

attention

63

This coding is non-arbitrary:


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64

Usage relates to assignment ofprominence attend to

this, it is important; highlighting Non-usage relates to backgrounding this information is

of the setting type, fleshing out contextual details, e.g.

provides a search domain

It is not suggested that the clause necessarily presents

backgrounded information

Greying, defocusing, or distancing is perhaps a better analogy

anti-highlighting

Prominence and backgrounding correlate with figure

and ground but they are not identical notions

This can be easily appreciated in non-linguistic


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65

This can be easily appreciated in non linguisticsemiosis:

Flashing light on signals engaged in police business,attention is drawn to the vehicle other drivers beware, asthis vehicle need not obey the usual rules

FLASH

INGLIGHTS

OFF

Whyhavetheflashing

lightsoff?

CATEGORYWhat typeof

vehicle?

Car

Justcruising;

unspecifiedactivity

FUNCTIONWhat function doesthevehicleserve?

Police vehicle

FLASHING

LIGHTS

ON

Why

turn

onthefla

shing

lights

?

Enga

gedin

polic

ework

Use

System

Flashing light offtells you thatthese guys are justcruising, looking

for trouble: police

functionbackgrounded

Applied to optional ergative case marking, we get an


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explanation for:

Use of the ergative highlights or foregrounds agentivity of

an agent Non-use of the ergative backgrounds its agentivity

I said there is a twist to the story

It is that either use or non-use might not convey anymeaning

One of them may be so frequent as to tell you nothing

So e.g. in Gooniyandi the ergative is so common that it is thenorm, and tells you nothing it does not highlight

Omission tells you something, as it is infrequent (c. 10% of the time)

Omission serves to background the agentivity of the agent66

This means that there is an additional factor that must


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be taken into account:

Markedness

Then we get the following scheme:

67

Use No meaning[prominent]Meaning[+prominent] No meaning[prominent]

Meaning[+prominent]

Non-use No meaning

[

back-grounded]

No meaning

[

back-grounded]

Meaning

[+back-grounded]

Meaning

[+back-grounded]

In my papers on the topic I show how some


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In my papers on the topic, I show how some

specific instances of non-use can be explained

in this way:

Now we are explaining the specific statement not

the general law (as above)

68

Two illustrative examples:


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69

p

Here the non-use of the ERG on ngidisuggests

pragmatically low agentivity of the speaker group.

Why, to what purpose would the speaker do this?

It primarily concerns the construal of the narrative world as one in

which:

The person being followed expended a lot of effort trying to find his

way home, but failed and died.

The followers easily tracked him, and found his body.

(1) aa, ngidi garndiwangoorroo, garndiwirri ngidi yoowooloo-yoorroo,

aa we many two we man-DUbaraj-jirr++a-yi, thinga, Gooniyandi

track-1excNOM+3sgACC+A-DU foot

We all we two Aborigines tracked him on foot.

The next example is the only instance in which an


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70

p y

inanimate Agent is not ergatively marked:

The reason: non-use of the ergative implicates low

agentivity, low potency

Lack of effect on the Undergoer as the next sentence says, it was

just a sprinkling of rain.

NB not lack of volitionality

(1) thinga gilba-yirr++di-yi / gamba / yilij-jin++afoot find-1excNOM+3sgACC+DI-DU water rain-1excACC+3sgNOM+A

garr garrwaroo /

after afternoon

We found his tracks, but it rained on us that afternoon. Gooniyandi

There are two important difficulties with


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Hempels story see Okasha 2002

First, what explains what?

The structure of explanations is symmetric:

Flagpole example provides a clear illustration

We can measure the height of a tree from:

Length of its shadow

Angle of the sun

We could use the height of the tree and angle of the sun toexplain the length of the shadow

In Hempels scheme, we could equally explain the height ofthe tree by the length of the shadow and the angle of the

sun! 71

Second difficulty is irrelevance


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Second difficulty is irrelevance

A young child is in a hospital ward full of pregnantwomen

One person in the ward is not pregnant, John, a

male

Child asks doctor Why isnt John pregnant

Doctor replies John has been taking birth control

pills for the past 3 years. People who take birth

control pills dont get pregnant. So John is notpregnant.

72

What the quack says may be true


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For some reason John has been taking birth control

pills

This would count as a viable explanation inHempels scheme

But few would regard this as a decent explanation

Most obviously the explanation is that John is a male

Whether he takes the pill or not is irrelevant

We need to at least add a criterion of relevance to Hempelsscheme

73

To return briefly to the first problem, we might propose arequirement of causality:


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q y

In a clear sense the height of the tree and the angle of the suncause the length of the shadow

Whereas the length of the shadow and angle of the sun can hardlycause the height of the tree

So we might suggest that to explain something is to identify

what the cause is

Height of a tree would be caused by things such as:

Genetic make up of the tree

The available resources in the environment

Not the length of the shadow

The causal criterion also explains why Johns taking the pill is notthe explanation of his not being pregnant

Clearly the cause of this situation is his sex 74

Things are not always the same in linguistics it is


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not clear that causality ought to be invoked in all

instances of explanation in our subject

In our language choice example, we explain

The choice of German to win the argument The winning of the argument by choice of German

In the case of optional ergative marking

The choice not to use the case-marker to background the

Agent

The backgrounding of the Agent by not using the ergative75

My opinion is that the situation here is differentto our flagpole and unpregnant male examples


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to our flagpole and unpregnant male examples

There is a good reason why

The type of linguistic phenomenon we are trying to explainhere concerns the linguistic sign

Recall Saussures model of the intrinsic relation between signifierand signified

No causal relation here

We can view the sign from either perspective, and thatswhat we are doing in our two alternative explanations oflanguage choice and case-marker use

Of course, I do not suggest that causal explanations have norole at all in linguistics

Only that causality is not the ultimate arbiter in all instances

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Conclusion


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Well be talking more about the philosophy of

science including linguistics later

What I try to do in this course is to encourage some ofthis self-awareness and reflexive thinking about oursubject, linguistics

And to see it in the wider contexts of both

Its history of development

Its ecology, the other disciplines that it interacts with

In short our interests are in the history and philosophy

of the science of linguistics 77

Conclusion

Finally, let us recall that linguistics straddles


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y, g

the science-humanities divide

A foot in both camps

Reflecting its status as a social science

And linguistics shows some peculiarities relative to the

hard sciences

Documents

Lecture 2, scientific reasoning and praxis.pptx