Showing posts with label Mathematics. Show all posts
Showing posts with label Mathematics. Show all posts

Thursday, 31 August 2023

Yaegan Doran On The Metafunctions In Mathematical And Chemical Symbolism

… we should be wary of metafunctions being considered a basic theoretical parameter for the description of semiotic resources in general.

A basic argument I put in a paper once was:
‘If we take metafunctionality to be the one of the broadest means by which these traditions [SFL/Social Semiotics] conceptualize the intrinsic functionality of semiotic resources, by simply assuming metafunctions across semiosis, we run the risk of homogenizing descriptions and making everything look like the first resource to be comprehensively described (i.e. English). That is, we risk watering down the specific functionality of each resource.’
Rather, following people working in language description at the time, I tried to tease these issues out for mathematical symbolism in the attached paper (and in more detail in my 2018 book Discourse of Physics), by attempting to ‘derive’ metafunctionality from axis (following Martin’s 2013 book on axis). Maths, I figured (with years of excellent help from many), would prove a useful point of contrast to language by virtue of regular common-sense comparisons that considered it to ‘be’ language/a language. But despite its comparability to language, I could find no evidence in the internal systemic/structural organisation of mathematical symbolism for an interpersonal component, and it was really pushing it to interpret an experiential component. But I tried to suggest that there was a major component comparable to the logical in language and a smaller independent one comparable to the textual. Nonetheless, I do think it much closer to language in this regard than most other resources, and so if even it struggles to fill out the full metafunctional complement, we should not assume it across the board (though metafunction is of course still a useful way in for analysis/application that is less concerned with descriptive/theoretical development – which I also tried to emphasise in the attached paper).

Along similar lines, Yu Zhigang followed this up by looking at the range of symbolism used in chemistry and concluded similarly – that the logical dominated, that there was little evidence for an interpersonal, that there was an even smaller textual component than maths, but there was in fact something comparable to an experiential. But he went a little further, and noted that some structuring principles that we often associate with interpersonal meaning in language – i.e. prosodic structure – occurred in various chemical symbolisms, but seemed to have become ‘ideationalised’ in that they were used to realise meaning related to field, not tenor.


Blogger Comments:

[1] To be clear, this is not just an argument against the metafunctional dimension of the theory, but against any dimension of the theory, and so against the theory itself, since in this view, using a theory that was devised for English, SFL, runs 'the risk of homogenising descriptions and making everything look like the first resource to be comprehensively described'. The same argument could be made against generalising Newton's theory of gravitation from falling apples to orbiting heavenly bodies, since it runs 'the risk of homogenising descriptions and making everything look like the first resource to be comprehensively described'. 

[2] To be clear, the metafunctions cannot be derived from axis, even if axis is properly understood. This is not least because they are independent dimensions, with different scopes, and organised according to different principles. Halliday & Matthiessen (2014: 20, 32):


That is, the local distinction between the paradigmatic and syntagmatic orders of axis entails nothing about the global distinctions between construing experience as meaning, enacting intersubjective relations as meaning, and creating text from the two.

For some of the theoretical misunderstandings of axis in Martin (2013), see the review here.

[3] To be clear, from the perspective of SFL Theory, mathematics is a contextual semiotic that is realised in language (e.g. algebraic equations) and a pictorial semiotic (e.g. geometric diagrams). The proof that equations, for example, are language is that, unlike non-language, they can be read aloud. This is because what is projected by saying, locutions, constitutes the lexicogrammatical stratum, and language is the only semiotic system with a stratified content plane. This is why bi-stratal systems, like pictorial semiotics, cannot be read aloud.

[4] To be clear, this is the logical fallacy known as the Argument from ignorance:

Argument from ignorance (from Latin: argumentum ad ignorantiam), also known as appeal to ignorance (in which ignorance represents "a lack of contrary evidence"), is a fallacy in informal logic. It asserts that a proposition is true because it has not yet been proven false or a proposition is false because it has not yet been proven true. This represents a type of false dichotomy in that it excludes the possibility that there may have been an insufficient investigation to prove that the proposition is either true or false.

Here Doran has misconstrued absence of evidence as evidence of absence. The evidence for the interpersonal metafunction in mathematical symbolism is manifold. For example, mathematical symbolism is language, so it enacts interpersonal meaning. As language, the equation E = mc² is a proposition realised by a declarative clause that can argued as valid or not whether it is expressed this way or as energy equals mass times the speed of light squared. If there were no interpersonal meaning in mathematical symbolism, then mathematicians would not be able to argue for or against their validity.


[5] To be clear, mathematical symbolism is deployed in many sciences precisely because it construes experience as meaning. As language, a mathematical equation is a figure of being realised by an intensive identifying relational clause, and the solving of an equation is the iterated elaboration of the clause until one or more unknown Tokens is decoded by reference to a Value.

[6] To be clear, the logical metafunction is concerned with the logico-semantic relations of expansion and projection, so it requires experiential meanings to relate logically to one another. Every equation is an intensive identifying clause that construes an elaborating logical relation between a Token and a Value, and the solving of an equation entails a clause complex in which all clauses are logically related through elaboration. The logical relation of extension, for example, is manifested in processes of addition and subtraction.

[7] To be clear, none of the metafunctions is independent of the others. Halliday & Matthiessen (1999: 532-3):
These three "metafunctions" are interdependent; no one could be developed except in the context of the other two. When we talk of the clause as a mapping of these three dimensions of meaning into a single complex grammatical structure, we seem to imply that each somehow "exists" independently; but they do not. There are — or could be — semiotics that are monofunctional in this way; but only very partial ones, dedicated to specific tasks. A general, all-purpose semiotic system could not evolve except in the interplay of action and reflection, a mode of understanding and a mode of doing — with itself included within its operational domain. Such a semiotic system is called a language.
More specifically, the textual metafunction requires the other metafunctions, since its function is to operationalise them. Halliday & Matthiessen (1999: 7-8, 398):
The textual metafunction is an enabling one; it is concerned with organising ideational and interpersonal meaning as discourse — as meaning that is contextualised and shared. … 
The function of the textual metafunction is thus an enabling one with respect to the rest; it takes over the semiotic resources brought into being by the other two metafunctions and as it were operationalises them…
Every mathematical equation is organised in terms of Theme and information; see [4] above.

[8] To be clear, given the explanatory power of the metafunctions, it would be more prudent to assume that they are a dimension of a semiotic system until it is proved otherwise. As explained above in [4], Doran mistook his inability to identify the metafunctions in mathematical symbolism for evidence that they are not a dimension of its systems. 

[9] To be clear, Yu Zhigang is Doran's collaborator, rather than a scholar working independently of Doran. More importantly, what is said above about mathematical symbolism also applies to chemical symbolism. For example:


∞

Sunday, 14 May 2023

David Kellogg On Mathematical Equations [3]

This kind of physics does cover Quantum Mechanics, Relativity, Maxwell, Newton, Galileo... The equations are mathematical — i.e. they can be read backwards and forwards, and they are exactly what Yaegan claimed: a different, non-linguistic, semiotic with its own anti-linguistic logic.


Blogger Comments:

[1] To be clear, this is true. In as much as an equation construes the identity of two participants, it can be 'read backwards and forwards'. However, the meanings construed in each case will be different, as demonstrated in the comments of the previous two posts.  

[2] See the comments of the previous two posts for evidence of the misunderstandings on which this conclusion is based.

From the perspective of Systemic Functional Linguistic Theory, mathematics is a field that is realised in (designed) language and (ideographic) pictorial semiotic systems. There are many reasons for interpreting mathematical equations as language rather than as a non-linguistic semiotic system. Two will be provided here.

First, mathematical equations entail a stratified content plane in which wordings realise meanings. On the SFL model, language is the only semiotic system with a stratified content plane (Halliday & Matthiessen 1999: 604):

This deconstrual of the content plane into two strata, referred to in the first chapter, is a unique feature of the post-infancy human semiotic…

The fact that the content plane of mathematical equations is stratified with a lexicogrammar is demonstrated by the fact that, unlike non-linguistic semiotic systems, they can be read aloud. On the SFL model, what is verbally projected is the wording level of content ('locutions').

Second, the only difference between

  1. a² + b² = c², and
  2. a squared plus b squared equals c squared, and
  3. its spoken form
is the mode of expression. All three construe the same wording and the same meaning. If it is claimed that the first is not language, then someone hearing the spoken form (3) would have to ask whether it corresponded to non-language (1) or to language (2), and interpret it differently accordingly.

On the other hand, the claim that mathematical equations are 'a different, non-linguistic, semiotic with its own anti-linguistic logic' goes nowhere in terms of explanatory potential. In contrast, treating mathematical equations as linguistic explains the solving of an equation as the iterated elaboration of an identity relation, and the solution of an equation as the decoding of an unknown Token.

∞

In dismissing all the evidence that invalidates his view, and simply maintaining his original stance, Kellogg has deployed the invincible ignorance fallacy.

Saturday, 13 May 2023

David Kellogg On Mathematical Equations [2]

Thanks, Chris--very insightful! I hadn't really parsed out voice and coding, as you can tell; I had them rather muddled, I'm afraid. The clarity of analysis is astonishing, and adds a lot of understanding.

However, the understanding I get from it only reinforces the distinction that Yaegan Doran made in his presentation. Halliday emphasises that relational clauses are never redundant. As you say, there is a difference between operative "equals" and receptive "equalled by", and there is likewise a difference between encoding"v= eE/m " and decoding ""eE/m = v". When my father writes:


(i.e. w = pressure = the Rayleigh formula, (integral of pressure term + integral of velocity term) in case the math doesn't come out in the mail....)

He is decoding and then decoding again. Not reversible.

But that's the old man doing physics, not math. When he does the math, the math itself really is redundant and reversible: "equals" and "is equalled by" really are completely equivalent, viewed as math. The encoding and the decoding, viewed as math and not as physics, are completely interchangeable. 

This to me suggests that Yaegan was right--that there is a qualitative difference between math as a semiotic system and language as a semiotic system. The former CAN be redundant, and that is the very essence of an equation. The latter is NEVER fully redundant, and that is the essence of a relational process.


Blogger Comments:

[1] This is misleading, because Halliday (1985, 1994) does not discuss relational processes in terms of redundancy. What he does say is that an identifying clause is not a tautology, and explains why this is so. Halliday (1994: 124):

In any ‘identifying’ clause, the two halves refer to the same thing; but the clause is not a tautology, so there must be some difference between them. This difference is one of form and function; or, in terms of their generalised labels in the grammar, of TOKEN and VALUE – and either can be used to identify the other.

To be clear, in the previous post, it was the introduction of the notion of asymmetry that was source of confusion, and in this post, the notion of redundancy plays that role.

[2] To be clear, it is true that the default direction of coding in a physics equation is decoding, but it is not true that this is not reversible. Such an equation becomes encoding when the Token is used to identify the Value, as when E is used to identify mc²:

Decoding

Encoding

[3] To be clear, in terms of meaning, equals and is equalled by are not completely equivalent. The operative voice of equals configures the participants as Token^Value, whereas the receptive voice of is equalled by, which is not used in mathematical formalisms, configures the participants as Value^Token. (The two also differ in choice of Subject and Theme.) What is consistent, irrespective of voice, is the identity of one participant (quantity) with another.

[4] To be clear, the direction of coding is distinct from the voice of an identifying clause. Operative and receptive clauses can be decoding or encoding. The direction of coding depends on which participant is used to identify the other: if the Value is used, then the clause is decoding; if the Token is used, then the clause is encoding.

To be clear, equations, whether used in mathematics or physics, can be decoding or encoding, though decoding is the default. However, it is not true that the two are equivalent in meaning, since they differ in which participant is used to identify the other. Again, what is consistent, irrespective of the direction of coding, is the identity of one participant (quantity) with another.

[5] See the above for evidence as to why this conclusion derives from multiple misunderstandings.

Friday, 12 May 2023

David Kellogg On Mathematical Equations [1]

David Kellogg wrote to sys-func on 24 April 2023 at 12:00:

I remember being vaguely dissatisfied with a presentation that Yaegon gave on this topic at University of Sydney, simply because he over-stressed the difference between mathematics and spoken language and at one or two points even argued for distinct origins in different kinds of logic. But now I see his point.

The terms "coding" and "decoding" imply asymmetry, and in fact asymmetry is the sine qua non of Halliday's understanding of relational processes. Understanding the grammar of a statement like "Tom is the tall one" (value-to-token, or encoding) or "Tom is the treasurer" (decoding) is really understanding that the sentence is NOT redundant — that the expressions are quite different when you reverse them. Encoding and decoding sentences are no more reversible than part-whole relationships, e.g. "All donkeys are animals" and "all animals are donkeys".  

But mathematical equations do not in themselves imply this asymmetry. For example, your equation could be reversed with very little or no difference in meaning,  "All donkeys are animals" is true and "all animals are donkeys" is false. But "c squared equals a squared plus b squared" is just as true and just as false as "a squared plus b squared equals c squared".

I was just discussing this with my father, who has been working on some data from the Parker Solar Probe, now entering the sun's corona. He wants to demonstrate that the heating of the solar wind  is caused (or at least could be caused) by the damping of ion acoustic waves in the solar wind. He pointed out to me that his papers are usually written in a mixture of mathematics and English. Here, for example, he is discussing how to determine the motion of a particle in an electric field. He says::

"dv/dt  = eE/m   

"So that

"v= eE/m "

Because the equations are embedded in language, they are not reversible. But the non-reversibility (that is, the fact that they are decoding relationships, with the token on the left and the value on the right) is an artefact of the language and not a logical consequence of the mathematics, just as the order of "a squared plus b squared equals c squared" is an artefact of our alphabet. 

 

Blogger Comments:

[1] This is misleading, because Halliday (1985, 1994) does not discuss relational processes in terms of asymmetry. What Kellogg refers to as 'asymmetry' is the functional difference between the two participants of an identifying process: Token vs Value and Identified vs Identifier. In a decoding clause, the asymmetry is Token/Identified vs Value/Identifier, whereas in an encoding clause, the asymmetry is Token/Identifier vs Value/Identified.

[2] To be clear, understanding the grammar of identifying clauses is understanding the functions that each clause constituent realises: Token or Value, Identifier or Identified.

[3] To be clear, encoding and decoding are reversible, but changing the direction of coding changes the meaning that the identity construes: Value encoded by reference to Token vs Token decoded by reference to Value.

[4] To be clear, part-whole relationships are reversible, in terms of coding, when they are construed as identifying rather than attributive. For example, the sports centre comprises four buildings is decoding in contexts where four buildings identifies the sport centre, and encoding in contexts where the sport centre identifies four buildings.


[5] To be clear, attributive clauses are not reversible in terms of the direction of coding because coding is restricted to construals of identity, whereas attributive clauses construe class membership (Halliday & Matthiessen 1999: 145-6), not an identity. (Trivially, reversing the participants in all donkeys are animals yields animals are all donkeys.)

[6] This is misleading, because it is untrue. If the participants in the clause a squared plus b squared equals c squared are reversed, all that is preserved is the identity of a squared plus b squared and c squared. The reversal changes not only what serves as Token and Value, but what serves as Theme and Rheme and what serves as Subject and Complement. Moreover, it can also involve a reversal the direction of coding:







[7] To be clear, the equations are reversible, though the reversal changes the functional role served by each nominal group in the equation, as explained in [6].

[8] To be clear, what makes these equations decoding is the conflation of Value with Identifier, not the sequence of Token and Value. If the Token on the left is used to identify the Value on the right, these equations are encoding.

[9] To be clear, the ordering Token^Value is given by the clause being operative in voice. But this is insufficient in itself to make the clause decoding; see [8]. 

Importantly, the mathematical equation uses the operative identifying clause as its template, and solving an equation involves repeatedly elaborating the equation, while preserving the identity relation, until each unknown is construed as a Token that is decoded by a Value.

[10] To be clear, this is the Pythagorean equation. The letters a and b stand for the two sides that meet at a right angle, and c stands for the hypotenuse.

Friday, 24 February 2017

Yaegan Doran Failing To Recognise The Interpersonal Metafunction In Mathematics

After Ruslana Westerlund wrote to Sysfling on 24 February 2017 at 7:52:
Hi all, I am curious about the usefulness of the Interpersonal metafunction in mathematics or science Or To what degree is TENOR important in mathematical discourse? If you know of anyone who has written on that, I would love any pointers or references.
Yaegan Doran replied to Sysfling on 24 Feb 2017 at 9:22:
Two places that discuss this are:
1) Kay O'Halloran's (2005) Mathematical Discourse: Language, symbolism and visual images. London: Continuum. 
- In this book, O'Halloran argues that the interpersonal metafunction in mathematics is greatly constrained in comparison to language, using this to explain certain patterns of mathematics in text. 
2) My PhD Thesis (soon to be in book form!) - Doran (2016) Knowledge in Physics through Mathematics, Image and Language. PhD Thesis, Department of Linguistics, The University of Sydney. 
- I go one step further than O'Halloran and argue that if we don't assume metafunctions occur for all semiotic resources, but rather seek to derive them from patterns in the system, there appears to be no evidence to recognise a distinct interpersonal metafunction - mathematical text patterns can be explained using purely ideational and textual systems.

Blogger Comments:

[1] To be clear, the metafunctions are an integral feature of SFL Theory, and the theory that Doran applied to mathematics was SFL Theory.

[2] Trivially, in theoretical terms, this is nonsensical. In SFL Theory, there are no "patterns in the system". The system represents the potential as an array of interrelated choices; patterns occur in the instantiation of the system.

[3] To be clear, if there were no interpersonal meaning in mathematics, mathematicians would not be able to argue about the validity of equations. Every equation of the type a + b = c is a proposition in terms of SPEECH FUNCTION, and a declarative clause in terms of MOOD; and every equation of the type let x = y is a proposal in terms of SPEECH FUNCTION, and an imperative clause in terms of MOOD. And this is true whether equations are realised phonologically, graphologically or in the formalisms peculiar to mathematics. If it were not true, then, on hearing a mathematical equation, an addressee would need to ask if it corresponded to the graphological expression or the mathematical formalism in order to ascertain whether or not the speaker was enacting interpersonal meaning.

Moreover, as the above suggests, the semiotic system that realises the cultural field of mathematics is language itself, or more specifically, registers (sub-potentials) of language. Language is the only semiotic system that can be read aloud — verbally projected as wordings — because language is the only semiotic system that has a stratum of wording (lexicogrammar).

For example:

E
=
mc2
Theme
Rheme
Given

New
Identified Token
Process: intensive
Identifier Value
Subject
Finite
Predicator
Complement
Mood
Residue

That is, the wording of every mathematical equation realises
  • a quantum of information
  • a figure of identity, and
  • a proposition (or proposal).