Saturday, June 26, 2010

God and Allah

I came across an internet discussion where they were earnestly discussing whether 'God' and 'Allah' have the same reference. There are three positions that a Christian - who believes that the name 'God' has a reference, and that it refers to the supernatural and all-powerful being who is mentioned in both the Old and New Testament - could take on this.

1. 'Allah' is an empty name, referring to nothing. If you are a Christian description theorist, you believe that all propositions containing 'Allah' have an implicit existence claim, and so are all false. If you are a (direct) referentialist Christian, you hold that all such propositions are senseless, since they cannot have truth-value.

2. 'Allah' refers to a supernatural and powerful (though not all powerful) being who is not identical with God. Thus all the claims of Islam implying an identity with God, such as this passage where Allah speaks to Adam and Eve, are false. Others may be true.

3. God and Allah are identical, but Islam says many things about God that are not true. The only true things are the those relating to the Old Testament. For example, Allah expels Adam and Eve from Eden: God did do this, and Allah is identical with God, ergo etc.

What if 'God' and 'Allah' are both empty names? Can we make sense of such claims to identity or difference? I favour a 'haecceity predicate' theory of proper names. Being the very individual that you are cannot be a property of you. Otherwise, as Bill Vallicella has pointed out, all sorts of absurdities follow. How could the the 'thisness' of an individual exist even if the individual whose thisness it is does not exist?

But if proper names are not descriptions, haecceity is clearly a predicate, since we can make a predicate from any proper name thus: '-- is identical to Socrates' (or 'God' or 'Allah'). That is the only way we can make sense of narratives like the Koran and the Old Testament, which mention the same supernatural being as the same being throughout.

Walters on Wikipedia

Excellent stuff here from Guy Walters in the Daily Telegraph. Has Wikipedia been overrun by left-wing trolls and junk historians? A "Left-leaning caucus of self-appointed editors who spend their days adjusting entries to fit in with their Weltanschauungen". Yes. And junk historians too. See also Oliver Kamm over at The Times.

Friday, June 25, 2010

A Milanese interjection

"Renzo arrived quite triumphant, and reported his success, finishing with a ahn? - a Milanese interjection which signifies - Am I a man or not? can you find a better plan? would it ever have entered your head? and a hundred other things".

The Betrothed (I Promessi Sposi) - Alessandro Manzoni.

Wednesday, June 23, 2010

William of Ockham

I said earlier that I would look at the Wikipedia article on William of Ockham*. This followed James Hannam's article in the Spectator deploring the fact that "the entry on Alhazen is 7,000 words long and bristles with 126 footnotes. Major figures of the medieval Christian world such as Ockham receive only 2,500 words". I commented that as well as being short, the article on Ockham was 'grossly misleading and incorrect'. How misleading? How inaccurate?

Life
The article begins with the observation that Ockham was born in Yorkshire and not, as most standard reference works suppose, in the village of Ockham in Surrey. This curiosity was inserted by an IP address on 3 May 2010. The philosopher C. Delisle Burns proposed this in 1916, but I can find no modern reference work that says this. Some sources say that he actually came from Woking, which had a similar spelling in medieval times, but Wikipedia does not mention this at all.
The rest of Ockham's biography is not so bad. It mentions the usual things about being summoned to Avignon, the controversy among the Franciscans, leaving Avignon in 1328 for exile at the court of Louis IV. Biographies in Wikipedia are generally accurate and well-written, mainly because, I suspect, there is no difficulty about which order to set out the facts. You start with a birth, and end with a death, and there is stuff in between.

Philosophical Thought
When we turn to the work of a great person, it is much more difficult, because this requires understanding the work, and making a judgment about which parts of the work to emphasis and explain. This is particularly important with medieval philosophers because, mostly, we have very little information about their lives. We have an intimate and deep knowledge of what they thought, because we have their work. But this requires understanding their work, and so we turn to the work of Ockham according to Wikipedia.

The odd section on his philosophical thought begins "In scholasticism, Okham advocated a reform both in method and in content, the aim of which was simplification" which is straightforwardly lifted out of the Catholic Encyclopedia, and which illustrates an important principle of Wikipedia (and much of the Internet) that essays about more serious subjects (i.e. subjects unconnected with Pokemon, Star Trek episodes and 'porn star' biographies) are taken from out of copyright sources like the Catholic Encyclopedia, or the 1911 Britannica. The irony that an ultra modern high-tech medium like the Internet, when it reflects anything of importance, reflects the sometimes obsolete views of 19th century scholars.

Nominalism
The section on nominalism is mostly lifted from the Catholic Encyclopedia, except for the paragraph at the end, where the abrupt change in style signals an entirely plagiarised excerpt from the Stanford Encyclopedia of Philosophy. The strange claim that Ockham has been called a "terminist", to distinguish him from a nominalist or a conceptualist, is from the Catholic Encyclopedia. Thus the article combines what is probably wrong ('terminism' can be consistent with nominalism**) with the section from the SEP which is intended for an academic audience, and is impenetrable out of context.

Natural Philosophy
The whole section on Natural Philosophy is eccentric and strange, with a convoluted discussion of impetus theory, of the views of Mach and Whitehead, and of "the president of the Birmingham Scientific Society, George Gore". This section was added on 7 June 2007 by an editor who was later banned for promoting strange and eccentric views on the history of science. You can read the discussion here. It illustrates an important principle of Wikipedia, namely that many editors are like this, and eventually end up banned. Their reason for editing Wikipedia is to promote some pet theory that they could not get published in an academic journal, but will always be accepted by 'the encyclopedia that anyone can edit'.

Ontological parsimony
The next section also mixes up passages from the Catholic Encyclopedia and the SEP, in a way that is highly misleading. It says that 'Ockham's Razor' is formulated by him as “For nothing ought to be posited without a reason given, unless it is self-evident (literally, known through itself) or known by experience or proved by the authority of Sacred Scripture.” The sentence is lifted verbatim from the SEP, except the SEP does not claim it is a formulation of the principle. Rather it suggests it is a sort of exception to the principle.

The original version of the article also copied the SEP claim that Ockham does not accept the Principle of Sufficient Reason. In a strange edit here made in 2006, an editor changes this to 'accepts' the principle. This is the same editor who added the plagiarised sections from the Catholic Encyclopedia, and whose contribution history suggests many such insertions, including a whole article about the late Scholastic philosopher Zabarella. Note that Wikipedia now contradicts itself, for the article on Ockham's Razor still retains the claim that Ockham did not accept the Principle of Sufficient Reason.

Theory of knowledge
The section on Ockham's theory of knowledge is clearly not plagiarised; the style is too amateurish and clumsy. As Dr Johnson once quipped: "Your work is both good and original. Unfortunately the parts which are good are not original, and the parts which are original are not good". (Or something like that).

Political Theory
The section on his political is reasonably written and seems reasonably accurate (although I am not an expert on this aspect of Ockham). It is however very brief, given the importance which experts attach to his work. if he really was one of the first medieval authors to advocate a form of separation between church and state, why does Wikipedia devote far less space (one sentence) than it does to the biography of a porn star?
Logic
The section on Ockham's logic is also remarkable for its brevity, considering that Ockham's fame rests mostly on his logical work, the magisterial and compendious Summa Logicae. It mentions only Ockham's anticipation of De Morgan's laws, and of many-valued logic. The latter claim is completely misleading. It illustrates the tendency of all reference work to emphasise the ideas of thinkers which anticipate, or seem to anticipate, later developments in philosophy and science, at the expense of other interesting ideas they may have had. No source is given; it probably comes from Ockham's defence of the 'traditional' interpretation of Aristotle (in Exposition in Librum Perihermenias I.6.15 - see the SEP article here). But it fails to mention that nearly all commentators on the famous 'sea battle' problem discussed by Aristotle were exercised by the problem of statements about future events, and by the possibility that such statements are neither true nor false. Thus the idea of a third 'truth value' did not originate with Ockham, and may have originated with Aristotle, depending on how you interpret Aristotle.
There is no discussion at all of how Ockham's nominalism is connected with his logic, of his use of supposition theory, nor of the way that Ockham really does anticipate the ideas of modern analytic philosophy in his view that you can address 'metaphysical' problems by carving up a sentence in the right way.

In summary: the Wikipedia article on William of Ockham, one of England's most illustrious and important philosophers, is woefully incomplete and inaccurate. It mixes blatant plagiarism with blatant falsehood. This is not surprising. What is surprising is the way that the respectable press eulogises Wikipedia, respectable institutions like the British Museum are entering into partnership with it, respectable donors like the Sloan Foundation are contributing large sums of money to it. This needs to change, although it is hard to see how.

* Permalink: version of 24 June 2010.
** Particularly in the case of Ockham's nominalism, defined as the view that we should not multiply entities according to the multiplicity of names.

Sunday, June 20, 2010

The Dumbest Generation

"According to recent reports from government agencies, foundations, survey firms, and scholarly institutions, most young people in the United States neither read literature (or fully know how), work reliably (just ask employers), visit cultural institutions (of any sort), nor vote (most can’t even understand a simple ballot). They cannot explain basic scientific methods, recount foundations of American history, or name any of their local political representatives. What do they happen to excel at is – each other. They spend unbelievable amounts of time electronically passing stories, pictures, tunes, and texts back and forth, savoring the thrill of peer attention and dwelling in a world of puerile banter and coarse images."

* http://www.dumbestgeneration.com/home.html
* http://www.latimes.com/entertainment/la-et-book5-2008jul05,0,6248930.story

Vaknin and Reagle on Wikipedia

I just found Sam Vaknin and Joseph Reagle. Vaknin is mostly repelled by Wikipedia, which he describes as a 'cult'. his website is here, and a few of his Wikipedia discussions here. Amidst a sizeable amount of ranting there are a few real gems.
As far as I can judge, the Wikipedia's coverage of the natural and exact sciences is pretty good. Its humanities articles are an unmitigated disaster, though: they are replete with nonsense, plagiarism, falsities, and propaganda. I know a bit about psychology, economics, philosophy, and the history of certain parts of the world. Articles dealing with these fields are utterly and sometimes dangerously unreliable.
Correct (I will give some examples over the next week). Wikipedia articles about set theory, pure mathematics, physics and other exact sciences are pretty good, as far as I can judge. But almost any article about the softer sciences and the humanities, and particularly philosophy, is a disaster.

Vaknin also has insightful things to say about teenagers and encyclopedias. He disparages the citation requirements of Wikipedia, which the teenage editors are obsessive about. The problem is that without credentials and education, an editor cannot tell the difference between good and bad sources. And as I commented here, they rarely bother to check the sources. If you understand the citation rules, you can make up any piece of nonsense you like, using a citation that does not support it in any way, particularly if you use academic papers and books which are not online, or obscure or out of print publications.

Vaknin says that even when the claims are 'verifiable' (i.e. backed up by reliable sources), research is not about hoarding facts (which Wikipedia generally is about, look for any article at random and you will soon come across a list - usually a list of silly things). "Wikipedia articles read like laundry lists of information gleaned from secondary sources". True research "is about identifying and applying context and about possessing a synoptic view of ostensibly unrelated data." (My emphasis).

Reagle, by contrast, is clearly a fan. Vaknin dismisses him entirely as a 'computer scientist'. I have only read his article on neutrality, and I was not impressed. It consists mostly of cursory remarks about 'neutrality', including a part about the X Windows System (what is that?), and a brief paragraph about the neutrality of Switzerland. It did not go on to ask the question implied by the title: whether Wikipedia is neutral. To do this, you need to take a reasonable sample of Wikipedia articles and compare them against some acceptable definition of neutrality. The article by James Hannam discussed in an earlier post did just that. Hannam took a definition of neutrality, namely, a topic balance which agreed roughly with the balance given by scholarly opinion, and found Wikipedia wanting. The entry on Alhazen is 7,000 words long and bristles with 126 footnotes. Major figures of the medieval Christian world such as William of Ockham* receive only 2,500 words.

I saw none of this critical approach in Reagle's essay. However, perhaps I should read more of his work and perhaps I am being unfair. The dispute is discussed in the Wikipedia signpost here, by Vaknin here. Reagle also has a weblog, and here is a video of one of his presentations.

*The entry on Ockham is also grossly misleading and incorrect. More later, perhaps.

The Fragility of Truth

Still musing on Wikipedia, I am revisiting Mill's On Liberty which has a fascinating insight into the nature of truth:

But, indeed, the dictum that truth always triumphs over persecution, is one of those pleasant falsehoods which men repeat after one another till they pass into commonplaces, but which all experience refutes. History teems with instances of truth put down by persecution. If not suppressed forever, it may be thrown back for centuries. [...] It is a piece of idle sentimentality that truth, merely as truth, has any inherent power denied to error, of prevailing against the dungeon and the stake. Men are not more zealous for truth than they often are for error, and a sufficient application of legal or even of social penalties will generally succeed in stopping the propagation of either. The real advantage which truth has, consists in this, that when an opinion is true, it may be extinguished once, twice, or many times, but in the course of ages there will generally be found persons to rediscover it, until some one of its reappearances falls on a time when from favourable circumstances it escapes persecution until it has made such head as to withstand all subsequent attempts to suppress it. (On Liberty, Chapter Two).
Quite right. The truth, being recognisable as true, will pop up again and again, and be suppressed again and again, until a favourable accident allows it to prevail and flourish. It is a piece of Wikipedia nonsense that the magic pixie-dust of 'crowdsourcing' will instantly drive out falsehood and all error. The crowd is often wrong. It is often right, of course, but even then it can rarely be bothered to go to Wikipedia to correct the error. Only the obsessive and the insane are likely to do that, and the truth is mostly lost on those.

Saturday, June 19, 2010

On Burley and Wild Oaks

This weeks' reading: "Walter Burley: His Life and Works" by Jennifer Ottman and Rega Wood (Vivarium 37pp. 1-23). There was no reference that I could find to Burley knowing Scotus while at Oxford (see my post here) but the article was full of some fascinating trivia about Burley. It opens with a one-paragraph summary that incorporates the intriguing statement that 'Burley found himself imprisoned for a forestry offence in 1336'.

When I summarise a subject that is large and broad, like someone's life, or a period in history, I try to imagine that every other piece of information about that subject has been annihilated except for my summary, which alone will be handed down to posterity. What are the really really important things that people in the future will need to know about this man, or this period in history? Ottman and Wood include the bit about the forestry offence. And why not? It captured my attention, and perhaps it tells us something about Burley.

There is more on p.19. Burley had been granted two oaks in Sherwood forest, near his rectory in Pytchely, by Queen Philippa (wife of Edward III and founder of Queen's College). When his men cut them down in 1336, Burley was arrested and imprisoned, aged 60. He was pardoned in December of the same year by Richard de Bury. How he came to be granted the oaks, why he cut them down, and why the offence was so serious as to deserve imprisonment, is not explained.

Another snippet is the inclusion of Burley's evidence that people undertake great risks for the sake of excessive enjoyment. 'Secundo est notandum quod multi superabundanter quaerunt delectationes qui tamen non fugiunt tristitias superabundanter. Multi enim multas tribulationes labores et pericula sustinent propter delectationes consequendas: ut patet de multis incontintentibus, qui propter delectationes corporales consequendas patiuntur frigora et calores et multa pericula ambulantes solitarii per noctes hyemales in tempore frigidissimo ad consequendum delectationes corporales et voluptates, et tales magis negociantur circa delectationes quam circa tristitias" (Expositio super decem libros Ethicorum Aristotelis, Venice 1500, 115ra).

I translate: 'Second, it must be noted that many superabundantly seek pleasure, who nevertheless do not superabundantly avoid suffering. For many [people] undergo much hardship, effort and danger because of the bodily pleasure that results. As is clear in the case of many immoderate [people] who, because of bodily pleasure, endure coldness and heat* and many dangers walking alone on winter nights in extreme cold, for the bodily pleasure and enjoyment that is to follow. And such [hardships] are more endured because of the pleasure, than on account of the suffering'.

I am intrigued by what sort of bodily pleasures he had in mind. And what events prompted this idea? Ottman and Wood conclude "clearly Burley was an engaging as well as a useful author".

* I don't follow this.

Frege's Point

What Geach calls 'Frege's point' is the claim that the same thought or proposition may occur now asserted, now unasserted. Frege expresses this very clearly in a short essay*, posthumously published, probably written in 1915, where he argues that asserting a sentence is a matter of the assertoric force with which the sentence is uttered, and that assertion is not the function of the word 'true'.

His argument is as follows. Uttering a sentence 'sea water is salt' merely expresses a thought. Nothing is meant to be asserted (behauptet werden solle). This becomes clear when turn the sentence into a that-clause: 'that sea-water is salty'. The that-clause does not assert anything. Or we could have the sentence spoken by an actor on a stage, where the actor does not speak with 'assertoric force' (or at least only seems to).

We can make this even clearer, he says, by adding the words 'it is true' to the expression 'that seawater is salty'. This forms a sentence that we can also turn into a that-clause: 'that it is true that sea-water is salty'. Thus the sense of the word 'true' does not make any essential contribution to the thought. If I assert 'it is true that sea-water is salty', I assert the same thing as if I assert 'sea-water is salty'. Thus the assertion is not to be found in the word 'true', but in the assertoric force with which the sentence is uttered.

Readers of this blog will recognise this as the thesis that William Vallicella has been defending from his website in Arizona. I shall discuss Frege's argument in my next post.

* "My Basic Logical Insights" (Posthumous Writings, transl. P. Long and R. White, 251-2. This is a translation of Nachgelassene Schriften 271-2).

Tuesday, June 08, 2010

Burley on empty names

I have been reading the early fourteenth century writer Walter Burley. He was working at the same place (Oxford) and the same time (late 1290s) as Scotus, and I wanted to understand how Burley approaches certain questions mentioned by Scotus. In his Questions on the Perihermenias, written in 1301, edited by Stephen Brown (Franciscan Studies 34 (1974) 200-295), question 4, Burley considers the question of whether existence is the same as essence, and in part of that question (4.44) he considers whether propositions like 'Caesar is a man' and 'a man is an animal' are eternally and necessarily true (even if Caesar no longer exists, and even if no man were existing).

He claims that nothing is actually in a real genus, unless it actually exists (nihil est in genere reali actualiter nisi actu exsistat). This (he says) follows from what Aristotle says in Metaphysics 6 at the end, where he divides being into being outside the mind, and a sort of diminished being in the mind, which he excludes from consideration. True being is divided into the ten categories, and so every category of being is true being outside the mind. Thus 'Caesar is a man' is false. He also mentions an argument that Scotus considers in his questions on the Perihermenias, namely Averroes' dictum that in substantial change, a thing loses its name and definition.

He considers the objection (4.54) that every proposition in which genus is predicated of species is necessary, such as 'A man is an animal' and 'a rose is a substance'. He replies that such propositions do not have to be necessary, nor true, unless the species necessarily has being. If 'man exists' is necesary and always true, then 'a man is an animal' is necessary and always true. Otherwise not.

This is opposite to the Scotus' conclusion. Scotus finds that 'Caesar is a man' is true, and he holds that essential propositions (which are sort of our 'analytic propositions') are eternally and necessarily.

Whether the two men met, we do not really know. One source (article "Walter Burley", by Mary Sommers, Blackwell Companion to Philosophy in the Middle Ages) claims that Walter attended Scotus' lectures in 1298, but does not identify her source (beyond the three secondary sources mentioned in the article, I am following these up).

On the question of whether existence and essence are the same, Walter agrees with the opinion of Godfrey of Fontaines (a writer that Scotus was certainly familiar with). Perhaps more about Godfrey later, when I finally track down the elusive De Wulf editions of his work.

Avicennian logic?

I only just discovered this. It is a Wikipedia 'Request for Comment' or RfC, which is rather like a court where Wikipedia editors pile on to each other, attack and eat their own. This one is quite extraordinary and concerns an editor 'Jagged 85' who has been systematically falsifying material in Wikipedia since he (or she) joined in 2005. The editor had a clear and consistent anti-Western agenda, systematically distorting source material in a way that untruthfully promoted Islamic (and also other non-Western) intellectual achievements, usually by claiming that a scientific developments or invention or discovery was made or anticipated by some non-Western philosopher or scientist.

It highlights a clear set of issues, as follows.

1. There is a large amount of material affected in Wikipedia, which is widely used as a reference work by millions of people, who trust it as a reliable source. The editor contributed to 8,115 pages, making 63,298 edits. Much of the problem material seems still to be there.

2. It demonstrates the role of Wikipedia in disseminating misleading and blatantly incorrect information across the web. The editor began work five years ago in December 2005, hist first edit claiming that "The Indus Valley civilization is in fact recognized as having been the first to develop urban planning. " Because many of his edits are now established, they have been reproduced and cited all over the internet. For example: Google 'Avicennian logic' (including the quotes) and it returns 6,000 sites (the top one being the Wikipedia article on 'Avicennism', where the phrase originates). Yet I am sure there is no formal system of logic known to scholars as 'Avicennian logic'. Avicenna made interesting contributions to logic, certainly, mostly in propositional logic, although this was originally developed by the ancient Greeks. But so did dozens of other middle-Eastern and Western writers, and the innovations of Avicenna do not compare in scale or impact with those of the high middle ages such as supposition theory, 'consequences' and so on. The article on 'Avicennism' says that "Avicennian logic had an influence on early medieval European logicians such as Albertus Magnus". Yet the idea that most influenced these scholars, including Albert, was Avicenna's distinction between essence and existence, which was a genuine innovation, and a departure from Aristotle. This idea had a profound impact, in different ways on Aquinas, Giles of Rome, Henry of Ghent, Scotus and eventually Ockham. But it is a metaphysical idea, not a logical one. As far as I am aware, no medieval writer discusses Avicenna's logic (as opposed to his commentary on the Metaphysics, which they frequently cite). Kneale's great work The Development of Logic mentions Avicenna twice, neither in connection with logic. Bochenski does not mention him at all. None of the articles in the main secondary sources on medieval philosophy mention Avicenna's logic (although they discuss his other achievements at length).

3. It proves a clear weakness in the Wikipedia 'verifiability principle'. The editor always provided reliable sources for their claims. However, examination revealed either blatant misrepresentation of the source, or a selective interpretation that went far beyond the author's meaning. For a long time no editors bothered to check these. The problem was amplified by his frequent use of scholarly works not available on the internet. Most of Wikipedia's editors are amateurs who have no access to a university library. Thus they cannot check a source from a journal, or an old or obscure book that would only be found in a library. Typical of his technique is this edit where he claims that "Avicenna developed an early theory of impetus, which he referred to as being proportional to weight times velocity, which was similar to the modern theory of momentum" citing Aydin Sayili (1987). "Ibn Sīnā and Buridan on the Motion of the Projectile", Annals of the New York Academy of Sciences 500. Yet the source attributes the theory to the fourteenth century French philosopher Buridan, not Avicenna. People trust Wikipedia because they believe the system of 'anyone can edit' allows for cross-checking and verification of references by a large group of users. Clearly, they should get out of this habit.

Monday, June 07, 2010

Thought is quick

"Enthymeme" is a form of argument where one or more of the assumptions is so obvious that it need not be stated. Suppose at a party my wife says "It's past eleven". I know what she means, which can be expressed by the following syllogism.

(Major) If it is past eleven and we are out, then leave now!
(Minor) It is past eleven and we are out
(Conclusion) Leave now!

She does not need to state the major premiss, nor even the conclusion, but I catch her drift. Note both the major and the conclusion contain an imperative. Arthur Prior investigated the logic of arguments containing imperatives in his paper "On Some Proofs of the Existence of God" , published in Papers in Logic and Ethics, Duckworth 1976.

Note also that the minor premiss is an assertion, and must be understood as such for the argument to be valid. If by contrast it meant something like "Would you like another large gin and tonic?" her conclusion would not follow. The point being, "linguistic meaning" is king. If it were not for the meaning we assign to expression types, we would not be able to express ourselves in ways like this, that superficially suggest that meaning constantly fluctuates, and that some expressions have no linguistic meaning.

Thomas Hobbes gives an entertaining example in Leviathan Chapter III (my emphasis).

"For in a discourse of our present civil war, what could seem more impertinent than to ask, as one did, what was the value of a Roman penny. Yet the coherence to me was manifest enough. For the thought of the war introduced the thought of the delivering up the king to his enemies; the thought of that brought in the thought of the delivering up of Christ; and that again the thought of the thirty pence, which was the price of that treason; and thence easily followed that malicious question; and all this in a moment of time—for thought is quick."

Sunday, June 06, 2010

The Value of Lawyers

"Great as are the evils which society still owes to lawyers, the lawyer-class has always been a civilizing agency".

Hastings Rashdall, The Universities of Europe in the Middle Ages, Oxford 1895, Vol II Part II, p. 708.

Saturday, June 05, 2010

The Prosentential Theory of Truth

In a comment to Vallicella here I mentioned an article on the pro-sentential theory in the Internet Encyclopedia of Philosophy, and said that the theory has 'some affinity' with the 'assertoric' theory of truth I have sketched out here (as well as fiercely defended at Vallicella's place.

Here, I will take some of the claims made for the prosentential theory in that article and compare them with the corresponding claims of the assertoric theory, to see how close the affinity is.

The Assertoric Theory
The assertoric theory of truth is that the copula 'is' of a simple declarative subject-predicate sentence, such as

Tom is running

contains two components. One is the copula, whose function is to join subject and predicate to form the 'content' of the sentence. The content we can signify by a noun phrase such as 'that Tom is running' or the verbal noun 'Tom's running'. The other is the assertoric component, whose function is to signal assertion, i.e. to signal that the person uttering the sentence is saying something capable of being true or false. We can make the internal structure of such a declarative sentence transparent by parsing it as follows:

It is true / that Tom is running

The Prosentential Theory compared to the Assertoric Theory
1. "According to the prosentential theory of truth, whenever a referring expression (for example, a definite description or a quote-name) is joined to the truth predicate, the resulting statement contains no more content than the sentence(s) picked out by the referring expression."

Although the theories are similar, the fundamental difference is that, according to the assertoric theory, the 'truth predicate' (actually the truth operator) operates on a noun phrase signifying the content of the sentence, not the sentence.

2. "The central claim of the prosentential theory is that ‘x is true’ functions as a prosentence-forming operator rather than a property-ascribing locution."

The central claim of the assertoric theory is that 'x is true' functions as an operator on a 'that'-clause that forms a normal sentence (not a 'prosentence'). It claims also that this operator is implicit, though not lexically visible, in a sentence that does not use the words 'is true'.

3. "According to the prosentential theory, the statement ‘p is true’ says no more than the statement ‘p,’

The corresponding claim in the assertion theory is that 'it is true that p' says no more than that p. I.e. 'It is true that Tom runs' says that Tom runs. However, the theory distinguishes between the operator 'it is true that', which operates on a sentence to produce another sentence (of equivalent meaning), the operator 'that' which operates on sentences to produce a noun phrase, and the operator 'it is true' which operates on 'that' clauses to form sentences. This is a crucial feature of the theory which is necessary to prevent the 'substitution problem'. If we substitute the noun phrase 'that Tom runs' for 'p' in 3 above, we get the nonsensical

(*) The statement 'that Tom runs is true' says no more than the statement 'that Tom runs'

which is nonsensical because 'that Tom runs' is not a statement, but a noun phrase. If by contrast we substitute the sentence 'Tom runs', we get

(**) The statement 'Tom runs is true' says no more than the statement 'Tom runs'

which is nonsensical because 'Tom runs is true' is not a well-formed sentence (it would be well-formed if we read it as 'that Tom runs is true', i.e. read the sentence as a that-clause, but then we are not substituting the same thing salva significatione. (To be fair, the IEP article does note the problem of substitution, but does not sufficiently explain how the prosentential theory overcomes it).

4. " The prosentential theory of truth counts as a ‘deflationary’ theory because it denies that any analysis of truth of the form "(x)(x is true iff x is F)" can be given, where ‘x is F’ expresses a property that is conceptually or explanatorily more fundamental than ‘x is true.’ "

The assertoric theory is also a deflationary theory on this criterion. According to the assertoric theory, 'is true' operates on a noun phrase (a that-clause) to form a sentence. This operator is present, explicitly or implicitly, in the main verb of every declarative sentence. It is fundamental to the semantics of the declarative sentence, and no more fundamental explanation is available.

5. "The prosentential theory of truth implies a solution to the liar paradox. Consider the following sentence.- This sentence is false - if it says something true, it is false ... if it says something false ... it is true. [... ] Some attempts to solve the liar paradox involve extreme measures. Tarski, for example, thought that the paradox could be avoided only by eschewing ‘semantically closed languages’ [...] Tarski succeeds in avoiding the basic form of the liar paradox—but only at a very high price. He must content himself with providing an account of ‘true-in-Li’ rather than an account of truth. And, since natural languages like English are semantically closed, Tarski’s theory also has the weakness of applying only to artificial languages. ... According to the prosentential theory, (43) is neither true nor false because it fails to pick up an anaphoric antecedent. Just as I cannot inherit my own wealth, a prosentence cannot inherit its content from itself. "

The assertoric theory solves the Paradox in essentially the same way. 'is true' is fundamentally an operator, not a predicate. When attached to a 'that'-clause, it does not predicate anything or attribute anything to anything named by the clause. It merely signals that the speaker is asserting the content signified by the clause. In the case of the Liar sentence, there is no content to be asserted. According to the assertoric theory, we must analyse every declarative sentence into a content-part, and an assertoric part. Thus the Liar sentence must be analysed as

What this sentence says is false.

where the content part is signified by 'What this sentence says', and the assertoric part to the denial 'is false'. But the sentence says nothing, because the attempt to locate a referent for it fails.

Friday, June 04, 2010

Deflationary theories of Truth

A common objection to deflationary theories of truth is sentences like 'Everything Tom says is true'. Analysing this as

(A) For all p, if he asserts p, then p.

results in incoherence when we attempt to substitute. If we substitute sentences like 'snow is white', we get

(B) If he asserts 'snow is white', then 'snow is white'.

which is nonsense. If we substitute propositional content, signified by a 'that' clause, we get

(C) If he asserts that snow is white, then that snow is white.

which is also nonsense. However, we can evade this difficulty along the lines I have suggested in earlier posts. The first insight is that 'it is true that' is a complex operator built from 'it is true', which operates on 'that' clauses to form declarative sentences, and 'that' which operates on sentences to form 'that' clauses. Then it is coherent to hold that the semantics of any declarative sentence can be represented formally as

(D) |- c

where the operator |- corresponds to the 'it is true' part, and 'c' to a that-clause. I.e. we parse 'it is true that Tom runs' as 'it is true / that Tom runs'. Then the problem sentence 'He is always right' can be analysed as

(E) If he says c, |- c

Suppose for example that he says that Tom runs. then c = that Tom runs (note I substitute a 'that' clause, not a sentence), and |- = 'it is true', as above. This yields

(F) If he says that Tom runs, it is true that Tom runs = if he says that Tom runs, Tom runs

which makes perfect sense.

Wednesday, June 02, 2010

Why truth is not a predicate

As I have argued below and elsewhere, the copula 'is', as in

(1) Tom is running

has a twofold function. The first is to join subject and predicate together into a single content that is expressible by the sentence. For example 'Tom's running' or 'that Tom runs'. The second - and this is something only a verb can do - is actually to express this content. Thus

(2) Tom's running is the case

or 'That Tom runs is a fact' or 'it is true that Tom runs'. Now as it happens the operator 'it is true' which we attach to the that-clause 'that Tom runs' or 'is the case' which we attach to 'Tom's running' also contains the verb 'is'. But this, I argue, is a grammatical accident. The 'is' in 'is the case' is mere filling. The operator 'is the case' is a unitary element of the sentence. It would be better expressed by a single verb 'isthecase' or 'itistrue'. If it is essentially complex, then of course it contains the verb 'is', and if it functions as a copula, then it will have the twofold function described above. 'the case' would be a predicate that we could attach to the subject 'Tom's running' to form the noun-phrase 'Tom's running being the case'. And we could further assert this to form a new sentence 'Tom's running being the case is the case' and so on ad infinitum.

This is obvious with 'is the case'. We are not tempted into supposing that 'the case' is a predicate that qualifies Tom's running in any way. It is less obvious with 'it is true'. It is more tempting to suppose that the noun-phrase 'that Tom is running' refers to some content, a thing, and that in forming 'that Tom is running is true' we are predicating 'truth' of this content. Bad things lie in that direction.

See also Maverick Philosopher for a different take on why truth is not a predicate