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Sunday, January 20, 2019

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Well my problem was ‘reality as it is in itself’. But you don’t mention the ‘in itself’ bit until the penultimate paragraph, where you write

What is true independently of anyone's asserting it is true in itself.

Does this mean that some thing can be true, but not independently of anyone asserting it? What does the qualifier ‘independently’ add? Surely whatever is true, is true ‘in itself’. You add.
What is true in itself is true in reality.

So some proposition could be true, but not true in reality? If ‘true’ simply means ‘true in reality’, we don’t really need the qualifier.

You also say

But that does not alter the fact that whenever one makes an assertion, the proposition one asserts is asserted to be true. Every sincere assertion aims at truth whether or not it hits the target.

But every lying assertion is also asserted to be true, even though the one making the assertion aims at falsity, as it were.

There is a separate problem lurking here which I have mentioned before. When does the act of assertion occur? The sentence is written on papyrus 1,000 BC, by a lone scribe. There is an act of writing. Is there an act of assertion? Difficult. Later on, the text is translated into a different language, say from Hebrew to Greek. I would say there has to be an act of understanding, but no act of assertion. Later, a scribe who has no comprehensive knowledge of Greek transcribes the text, symbol by symbol, as though copying a drawing. No act of understanding. Finally I read it. The text tells me that Moses died in Moab. There is an act of understanding, and an act of communication. But is there an act of assertion?

Again: when does the act of assertion occur, in any situation where the utterance or inscribing takes place at a different time from the act of understanding?

Morning Bill,

What about statements (are they assertions?) made in the context of a hypothetical slated for reductio? Example:

Suppose there is an intra-Mercurial planet---call it Vulcan---whose gravity is responsible for the advance in the perihelion of Mercury.
(*) Vulcan's diameter exceeds a certain minimum, d.
Statement (*) seems to aim for truth but truth 'in some alternative reality'. It's not clear how to assign it a truth value in this reality.

Good morning, David.

First of all, do you agree that if one asserts a conditional or hypothetical proposition, one does not thereby assert either the antecedent or the consequent? If yes, then (*) des not come within the purview of my concerns above.

Gotta go.

Hello Bill,

Well, I'd certainly say that from p-->q we can infer neither p nor q. But I'm interested in whether you would say that a statement appearing within the scope of the 'suppose there is...' statement was asserted. For example, the statement 'if an intra-mercurial planet has a diameter greater then D then it is visible' , for some D, may well appear.

David,

No. Supposing is a different speech act from asserting. To suppose that p is not to assert that p but to 'entertain' it, perhaps to see what follows from it. If I can derive a contradiction from it, then I can assert that the content of my supposition is false.

For example, to prove that the null set is unique using RAA, I might suppose that t is not unique, that there are two or more null sets. When after a couple of easy steps I arrive at a contradiction, I then assert that the null set is unique.

And I agree with Bill that the sentence 'suppose that p' involves no assertion that p, whereas ‘p’ does involve the assertion that p, but where I disagree is that the distinction involves a ‘speech act’ or anything like that. For the same thing may happen where there is no speech, or no act, or neither. Sign language may allow the same distinction, or we could hold up a placard with the statement or the supposition, as in the Dylan video. So there doesn’t have to be any speech.

Nor does there have to be any act. ‘Moses died in Moab’ was written more than 2,000 years ago, so the act of writing is long past. I concede there is an act of understanding when we read that sentence, but that is hardly a 'speech act'. The distinction in my view is purely down to signification. The sentences ‘p’ and ‘suppose that p’ are different, and have different meanings or significations, and the difference is that the first expresses the proposition that p, the second does not. Actually the second expresses a command, if we are going to get picky.

Bill has yet to give any argument or evidence that the distinction is not signified. Simply repeating the mantra 'people assert propositions' is not enough. I say 'sentences express propositions', for which I have given ample evidence.

And yet we apply the rules of inference to the statements that appear within the scope of 'suppose that p' just as we would if they were outside. It's as if assertion and truth were irrelevant within the scope of the hypothetical. This has long puzzled me.

Ed,

One of the main points I am trying to get across to you is that asserting is something that people do, whether by speech, by writing, by sign language.

>> ‘Moses died in Moab’ was written more than 2,000 years ago, so the act of writing is long past.<<

No doubt. But somebody had to think that thought and write it down, thereby asserting that Moses died in Moab. Do you deny that?

>>No doubt. But somebody had to think that thought and write it down, thereby asserting that Moses died in Moab. Do you deny that?

I would say, they wrote something down which if read would communicate the proposition that Moses died etc. The subject of the verb 'communicate' is the stuff written down, not the scribe. The problem that if the scribe is making the assertion at the time of writing, in what sense does he now assert this? He is dead, and cannot perform any act, let alone assertion. Does the assertion take place when no one is reading that passage? Sounds absurd. Does it take place only at the moment someone is reading? But perhaps thousands of people are reading that passage now. Are you saying that the scribe is now asserting, a thousand times, that Moses died etc?

I would say that when anyone reads it, the scribe has (perfect tense) communicated that Moses died. In much the same sense that we say someone has left some money in their will.

Do you disagree?

David:
>> It's as if assertion and truth were irrelevant within the scope of the hypothetical. This has long puzzled me.

How about 'if it is true that p, then it is true that q'?

Or 'it is not true that p, but if it were true, it would be true that q'. Here the truth of p is expressed.(Expressed by what, you ask? By the language, I say).

Ed, Bill,
My concern is with the assertion status and truth value of the statements that appear in the scope of the hypothesis. A typical RAA looks like this:

Suppose p
   q
   r
   s
   :
   z
   ~z
ergo, ~p
When we rehearse the argument we treat p, q, r... in no way different from statements outside the scope of the Suppose. The sequence p, q, r... might be lengthy and while we focus on the inferences between them we see them as asserted and having truth values. Yet when we reach ~z we realise that it's not possible to assign consistent truth values to all of these statements, and I'm not exactly comfortable with that. One way of resolving the difficulty is to abandon assertion and truth value and see the whole business in purely formal terms as a calculus over symbols. But I'm not entirely happy with that, either.

>>One of the main points I am trying to get across to you is that asserting is something that people do

Yes I get that. It's a slogan borrowed from the old ordinary language movement. It is appropriate for the situation where someone utters a declarative sentence in the presence of another person who understands the language. It is wholly inadequate for any other situation.

I gave the example by email of a fire alarm. The alarm means 'there is a fire in the building'. An assertion has taken place, that there is a fire. But it is triggered by a sensor in the building. So asserting is not just something people do.

>>The sequence p, q, r... might be lengthy and while we focus on the inferences between them we see them as asserted and having truth values.

I don't see that. I am thinking 'suppose that p, suppose that q ...' etc.

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