Archive for the 'Philosophy of Language' Category

Hackathon life


At the first Internet of Things and Distributed Ledgers Hackathon, Barclays Rise Hackspace, Notting Hill, London, 7 November 2015.

Political talk

James Button, one-time speech-writer to former Australian Prime Minister Kevin Rudd, wrote this in his recent book:

When Rudd spoke at the Department’s Christmas party, he had sketched a triangle in the air that distilled the work of producing a policy or speech into a three-point plan:  where are we now; where do we want to go and why; how are we going to get there?  The second point – where do we want to go and why – expressed our values, Rudd said. It was a simple way to structure a speech and I often used it when writing speeches in the year to come.” (Button 2012, page 55, large print edition).

Reading this I was reminded how inadequate I had found the analysis of political speech propounded by anthropologist Michael Silverstein in his short book on political talk (Silverstein 2003).   He seems to view political speech as mere information transfer, and the utterances made therefore as essentially being propositions – statements about the world that are either true or false.   Perhaps these propositions may be covered in rhetorical glitter, or presented incrementally, or subtly, or cleverly, but propositions they remain.   I know of no politician, and I can think of none, who speaks that way.   All political speeches (at least in the languages known to me) are calls to action of one form or another.   These actions may be undertaken by the speaker or their political party – “If elected, I will do XYZ” – or they may be actions which the current elected officials should be doing  – “Our Government should be doing XYZ.”     Implicit in such calls is always another call, to an action by the listener:  “Vote for me”.    Even lists of past achievements, which Button mentions Rudd was fond of giving, are implicit or explicit entreaties for votes.

Of course, such calls to action may, of necessity, be supported by elaborate propositional statements about the world as it is, or as it could be or should be, as Rudd’s structure shows.   And such propositions may be believed or not, by listeners.  But people called to action do not evaluate the calls they hear the way they would propositions.  It makes no sense, for instance, to talk about the “truth” or “falsity” of an action, or even of a call to action.   Instead, we assess such calls on the basis of the sincerity or commitment of the speaker, on the appropriateness or feasibility or ease or legality of the action, on the consequences of the proposed action, on its costs and benefits, its likelihood of success, its potential side effects, on how it compares to any alternative actions, on the extent to which others will support it also, etc.

What has always struck me about Barack Obama’s speeches, particularly those during his first run for President in 2007-2008,  is how often he makes calls-to-action for actions to be undertaken by his listeners:  He would say “We should do X”, but actually mean, “You-all should do X”, since the action is often not something he can do alone, or even at all.  “Yes we can!” was of this form, since he is saying, “Yes, we can take back the government from the Republicans, by us all voting.”    From past political speeches I have read or seen, it seems to me that only JFK, MLK and RFK regularly spoke in this way, although I am sure there must have been other politicians who did.  This approach and the associated language comes directly from Obama’s work as a community organizer: success in that role consists in persuading people to work together on their own joint behalf.  Having spent lots of time in the company of foreign aid workers in Africa, this voice and these idioms were very familiar to me when I first heard Obama speak.

Rudd’s three-part structure matches closely to the formalism proposed by Atkinson et al. [2005] for making proposals for action in multi-party dialogs over action, a structure that supports rational critique and assessment of the proposed action, along the dimensions mentioned above.


K. Atkinson, T. Bench-Capon and P. McBurney [2005]: A dialogue-game protocol for multi-agent argument over proposals for action.   Autonomous Agents and Multi-Agent Systems, 11 (2): 153-171.

James Button [2012]: Speechless:  A Year in my Father’s Business.  Melbourne, Australia:  Melbourne University Press.

Michael Silverstein [2003]:   Talking Politics:  The Substance of Style from Abe to “W”.  Chicago, IL, USA:  Prickly Paradigm Press.

The epistemics of London Underground announcements

What the announcer at the London underground station said this morning:

  • We have no reports of unplanned station closures.

What he did not say:

  • There are no reports of unplanned station closures.   Perhaps he did not say this because there could be such reports, which he or his station have yet to receive.  In either case – whether he had received such reports or not – he would not be able to state truthfully that there were no such reports.
  • There are no unplanned station closures.  Perhaps he did not say this because stations could be closed without this fact having yet been reported, and so without his knowing this about them.
  • No stations are closed.  Perhaps he did not say this because stations could be closed intentionally and with forethought, for instance, for scheduled maintenance.   Indeed, such a statement would in fact be false as there several London underground stations which are permanently closed, eg Aldwych Station.
  • All stations are open.   Perhaps he did not say this because stations could be neither open nor closed, for example when they are in transition from one state to the other, or else due to quantum uncertainty.

One has to be so careful in what one says, as I have remarked before.

The semantics of communication

A recent incident reminded me of Nicolas Negroponte’s argument that a single wink (one bit of information) may communicate effectively between two people, and yet require a thousand words to explain to someone else.

The scene: A small group meeting of 5 people (an EC research proposal review meeting), none of whom know each other or have worked together before. The meeting chair, let’s call her Alice, wants another person, Bob, to endorse a particular outline plan of action. This plan does not entail him doing anything, but he is nonetheless resistant, and puts forward both reasonable and unreasonable justifications for not endorsing the plan. Alice tries another couple of arguments, but each of these meets similar resistance from Bob. At this point, Alice does not know what the rest of us think about her plan or Bob’s opinion of it.

Having heard the two sides, I decide that Alice is correct and that Bob should endorse the plan. But Alice, I believe, has not used the best arguments in favour of his doing so, and thus I add my voice to her side, giving a new argument to justify Bob changing his opinion. My argument fails with Bob, but leads Alice to think of a further argument, and both our arguments together have a consequence that completely rebuts Bob’s reasonable main defence for non-endorsement. When she presents this line (my argument + her argument + their joint consequence) to him, Bob wilts and agrees to endorse Alice’s plan.

However, just before Alice presents this line to Bob, she shoots me a quick look of conspiratorial deviousness, as if to say, “We got him, you and I, and in getting him, we have demonstrated our intellectual superiority and mental agility over him. Although we just met, we two have conspired effectively and enjoyably together.” It was a look of the most profound respect – a connection between equals, in the presence of someone whose persistent and unreasonable resistance to a reasonable proposal had revealed himself to be less committed to the agreed purpose of the meeting.  And receiving it was the most profound of pleasures.

Command Dialogs

Three years ago, in a post about Generation Kill and Nate Fick, I remarked that military commands often need dialog between commander and commandee(s) before they may be rationally accepted, and/or executed.   Sadly, a very good demonstration of the failure to adequately discuss commands (or purported commands) in a complex (police) action is shown by a report on the UC-Davis Pepper Spray incident.  

Management textbooks of a certain vintage used to define management as the doing of things through others.   The Pepper Spray example clearly shows the difficulties and challenges involved in actually achieving such vicarious doing in dynamic and ambiguous situations.  And the poverty of Philosophy is not better shown than by the fact that the speech act of commanding has barely been studied at all by philosophers, obsessed these last 2,350 years with understanding assertions of facts.  (Chellas, Hamblin, Girle and Parsons are exceptions.)

Michael Dummett RIP

The death has just occurred of the philosopher Michael Dummett (1925-2011), formerly Wykeham Professor of Logic at Oxford.    His writings on the philosophy of language and the philosophy of mathematics have influenced me, particularly his thorough book on intuitionism.   Having been educated by pure mathematicians who actively disparaged intuitionist and constructivist ideas, I found it liberating to see these ideas taken seriously and considered carefully.  The precision of Dummett’s writing and thought clearly marked him out as a member of the Matherati, as also his other formal work, such as that on voting procedures.

POSTSCRIPT (2012-01-21):  The logician Graham Priest remembers Dummett as follows:

It is clear that Dummett was one of the most important — perhaps the most important — British philosopher of the last half century. His work on the philosophy of language and metaphysics, inspired by themes in intuitionist logic, was truly groundbreaking. He took intuitionism from a somewhat esoteric doctrine in the philosophy of mathematics to a mainstream philosophical position.

Perhaps his greatest achievement, as far as I am concerned, was to demonstrate beyond doubt the intellectual respectability of a fully-fledged philosophical position based on a contemporary heterodox logic. Philosophers in the United Kingdom, even if they do not subscribe to Dummett’s views, no longer doubt the possibility of this. Dummett had an influence in Australia, too. It was quieter there than in the U.K., but the relevant philosophical lesson was amplified by logicians who endorsed heterodox logics of a different stripe (for which, I think, Dummett had little sympathy). The result has been much the same.

In the United States, though, Dummett had virtually no significant impact. Indeed, I am continually surprised how conservative philosophy in the United States is with regard to heterodox logics. It is still awaiting a Dummett to awaken it from its dogmatic logical slumbers.

Graham Priest, City University of New York Graduate Center, and the University of Melbourne (Australia)


His Guardian obituary is here.  An index to posts about members of the Matherati can be found here.

M. Dummett [1977/2000]: Elements of Intuitionism. (Oxford: Clarendon Press, 1st edition 1977; 2nd edition 2000).

Automating prayer

I have recently re-read Michael Frayn’s The Tin Men, a superb satire of AI.  Among the many wonderful passages is this, on the semantic verification problem of agent communications:

“Ah,” said Rowe, “there’s a difference between a man and a machine when it comes to praying.”   “Aye. The machine would do it better. It wouldn’t pray for things it oughtn’t pray for, and its thoughts wouldn’t wander.”

“Y-e-e-s. But the computer saying the words wouldn’t be the same . . .”

“Oh, I don’t know. If the words ‘O Lord, bless the Queen and her Ministers‘ are going to produce any tangible effects on the Government, it can’t matter who or what says them, can it?”

“Y-e-e-s, I see that. But if a man says the words he means them.”

“So does the computer. Or at any rate, it would take a damned complicated computer to say the words without meaning them. I mean, what do we mean by ‘mean’? If we want to know whether a man or a computer means ‘O Lord, bless the Queen and her Ministers,’ we look to see whether it’s grinning insincerely or ironically as it says the words. We try to find out whether it belongs to the Communist Party. We observe whether it simultaneously passes notes about lunch or fornication. If it passes all the tests of this sort, what other tests are there for telling if it means what it says? All the computers in my department, at any rate, would pray with great sincerity and single-mindedness. They’re devout wee things, computers.” (pages 109-110).


Michael Frayn [1995/1965]: The Tin Men (London, UK: Penguin, originally published by William Collins, 1965)

A salute to Charles Hamblin

This short biography of Australian philosopher and computer scientist Charles L. Hamblin was initially commissioned by the Australian Computer Museum Society.

Charles Leonard Hamblin (1922-1985) was an Australian philosopher and one of Australia’s first computer scientists. His main early contributions to computing, which date from the mid 1950s, were the development and application of reverse polish notation and the zero-address store. He was also the developer of one of the first computer languages, GEORGE. Since his death, his ideas have become influential in the design of computer interaction protocols, and are expected to shape the next generation of e-commerce and machine-communication systems.

Continue reading ‘A salute to Charles Hamblin’

Dialogs over actions

In the post below, I mentioned the challenge for knowledge engineers of representing know-how, a task which may require explicit representation of actions, and sometimes also of utterances over actions.  The know-how involved in steering a large sailing ship with its diverse crew surely includes the knowledge of who to ask (or to command) to do what, when, and how to respond when these requests (or commands) are ignored, or fail to be executed successfully or timeously.

One might imagine epistemology – the philosophy of knowledge – would be of help here.  Philosophers, however, have been seduced since Aristotle with propositions (factual statements about the world having truth values), largely ignoring actions, and their representation.   Philosophers of language have also mostly focused on speech acts – utterances which act to change the world – rather than on utterances about actions themselves.  Even among speech act theorists the obsession with propositions is strong, with attempts to analyze utterances which are demonstrably not propositions (eg, commands) by means of implicit assertive statements – propositions  asserting something about the world, where “the world” is extended to include internal mental states and intangible social relations between people – which these utterances allegedly imply.  With only a few exceptions (Thomas Reid 1788, Adolf Reinach 1913, Juergen Habermas 1981, Charles Hamblin 1987), philosophers of language have mostly ignored utterances  about actions.

Consider the following two statements:

I promise you to wash the car.

I command you to wash the car.

The two statements have almost identical English syntax.   Yet their meanings, and the intentions of their speakers, are very distinct.  For a start, the action of washing the car would be done by different people – the speaker and the hearer, respectively (assuming for the moment that the command is validly issued, and accepted).  Similarly, the power to retract or revoke the action of washing the car rests with different people – with the hearer (as the recipient of the promise) and the speaker (as the commander), respectively.

Linguists generally use “semantics” to refer to the real-world referants of syntactically-correct expressions, while “pragmatics” refers to other aspects of the meaning and use of an expression not related to their relationship (or not) to things in the world, such as the speaker’s intentions.  For neither of these two expressions does it make sense to speak of  their truth value:  a promise may be questioned as to its sincerity, or its feasibility, or its appropriateness, etc, but not its truth or falsity;  likewise, a command  may be questioned as to its legal validity, or its feasibility, or its morality, etc, but also not its truth or falsity.

For utterances about actions, such as promises, requests, entreaties and commands, truth-value semantics makes no sense.  Instead, we generally need to consider two pragmatic aspects.  The first is uptake, the acceptance of the utterance by the hearer (an aspect first identified by Reid and by Reinach), an acceptance which generally creates a social commitment to execute the action described in the utterance by one or other party to the conversation (speaker or hearer).    Once uptaken, a second pragmatic aspect comes into play:  the power to revoke or retract the social commitment to execute the action.  This revocation power does not necessarily lie with the original speaker; only the recipient of a promise may cancel it, for example, and not the original promiser.  The revocation power also does not necessarily lie with the uptaker, as commands readily indicate.

Why would a computer scientist be interested in such humanistic arcana?  The more tasks we delegate to intelligent machines, the more they need to co-ordinate actions with others of like kind.  Such co-ordination requires conversations comprising utterances over actions, and, for success, these require agreed syntax, semantics and pragmatics.  To give just one example:  the use of intelligent devices by soldiers have made the modern battlefield a place of overwhelming information collection, analysis and communication.  Lots of this communication can be done by intelligent software agents, which is why the US military, inter alia, sponsors research applying the philosophy of language and the  philosophy of argumentation to machine communications.

Meanwhile, the philistine British Government intends to cease funding tertiary education in the arts and the humanities.   Even utilitarians should object to this.


Juergen  Habermas [1984/1981]:   The Theory of Communicative Action:  Volume 1:  Reason and the Rationalization of Society.  London, UK:  Heinemann.   (Translation by T. McCarthy of:  Theorie des Kommunikativen Handelns, Band I,  Handlungsrationalitat und gesellschaftliche Rationalisierung. Suhrkamp, Frankfurt, Germany, 1981.)

Charles  L. Hamblin [1987]:  Imperatives. Oxford, UK:  Basil Blackwell.

P. McBurney and S. Parsons [2007]: Retraction and revocation in agent deliberation dialogs. Argumentation, 21 (3): 269-289.

Adolph Reinach [1913]:  Die apriorischen Grundlagen des bürgerlichen Rechtes.  Jahrbuch für Philosophie und phänomenologische Forschung, 1: 685-847.

Syntax Attacks

Thanks to the ever-watchful Normblog, I encounter an article by Colin Tatz inveighing against talk about sport.  Norm is right to call Tatz to account for writing nonsense – talk about sport is just as meaningful as talk about politics, history, religion, nuclear deterrence, genocide, or any other real-world human activity.  Tatz says:

Sport is international phatic but also a crucial Australian (male) vehicle. It enables not just short, passing greetings but allows for what may seem like deep, passionate and meaningful conversations but which in the end are unmemorable, empty, producing nothing and enhancing no one.

Unmemorable?! Really?   What Australian could forget Norman May’s shouted “Gold! Gold for Australia! Gold!” commentary at the end of the men’s 400-metre swimming medley at the 1980 Olympics in Moscow.  Only a churlish gradgrind could fail to be enhanced by hearing this.   And what Australian of a certain age could forget the inimitable footie commentary of Rex Mossop, including, for example, such statements as,  “That’s the second consecutive time he’s done that in a row one straight after the other.” Mossop’s heat-of-the-moment sporting talk was commemorated with his many winning places in playwright Alex Buzo’s Australian Indoor Tautology Pennant, an annual competition held, as I recall,  in Wagga Wagga, Gin Gin and Woy Woy (although not in Woop Woop or in The Never Never), before moving internationally to exotic locations such as Pago Pago, Xai Xai and Baden Baden.  Unmemorable, Mr Tatz?  Enhancing no one?  Really?  To be clear, these are not memorable sporting events, but memorable sporting commentary.   And all I’ve mentioned so far is sporting talk, not the great writers on baseball, on golf, on cricket, on swimming,  . . .

But as well as misunderstanding what talk about sport is about and why it is meaningful, Tatz is wrong on another score.   He says:

But why so much natter and clatter about sport? Eco’s answer is that sport “is the maximum aberration of ‘phatic’ speech”, which is really a negation of speech.

Phatic speech is meaningless speech, as in “G’day, how’s it going?” or “have a nice day” or “catch you later” — small talk phrases intended to produce a sense of sociability, sometimes uttered in the hope that it will lead to further and more real intercourse, but human enough even if the converse goes no further.

Phatic communications are about establishing and maintaining relationships between people.  Such a purpose is the very essence of speech communication, not its negation.  Tatz, I fear, has fallen into the trap of so many computer scientists – to focus on the syntax of messages, and completely ignore their semantics and pragmatics.    The syntax of messages concerns their surface form, their logical structure, their obedience (or not) to rules which determine whether they are legal and well-formed statements (or not) in the language they purport to arise from.  The semantics of utterances concerns their truth or falsity, in so far they describe real objects in some world (perhaps the one we all live in, or some past, future or imagined world),  while their pragmatics concerns those aspects of their meaning unrelated to their truth status (for example, who has power to revoke or retract them).

I have discussed this syntax-is-all-there-is mistake before.    I believe the root causes of this mistaken view are two-fold: the mis-guided focus of philosophers these last two centuries on propositions to the exclusion of other types of utterances and statements (of which profound error Terry Eagleton has shown himself guilty), and the mis-guided view that we now live in some form of Information Society, a view which wrongly focuses attention on the information  transferred by utterances to the exclusion of any other functions that utterances may serve or any other things we agents (people and machines) may be doing and aiming to do when we talk.   If you don’t believe me about the potentially complex functionality of utterances, even when viewed as nothing more than the communication of factual propositions, then read this simple example.

If communications were only about the transfer of explicit information, then life would be immensely less interesting.  It would also not be human life, for we would be no more intelligent than desktop computers passing HTTP requests and responses to one another.