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John Jones · Guest

First a definition:
A 'disjunction' "A V B " read as "A or B " is false if both A and B are
false. In all other cases it is true.

The problem that arose with the connective 'and' also arises with a
disjunction.

Simply, for both disjunction and conjunction, whatever the truth values
of A and B ARE (plural case), the nature of the third element that IS
(singular case) both A and B is underdetermined whether or not that
element is true or false.

The third, unspecified element in conjunction and disjunction can be
seen in implicit form in the diagrams used to teach logical conjunction
and disjunction. Thus we have the Venn overlap and the gate of the logic
gate.

I have to put this as a challenge. What is the nature of the object that
IS 'A and B' in a conjunction or disjunction of the elements 'A' and 'B'?

Herbert Newman · Guest

On Fri, 24 Oct 2008 20:43:59 +0100 John Jones wrote:

[quote]
[...]

[/quote]
Did you ever seek professional help?

Herb

John Jones · Guest

Herbert Newman wrote:
[quote]On Fri, 24 Oct 2008 20:43:59 +0100 John Jones wrote:

[...]

Did you ever seek professional help?

Herb
[/quote]
I should be grateful, you know. Herbet has pushed my post back to the
top of the pile of new posts. And to show my gratitude I think that it
deserves a reply.

John Jones · Guest

John Jones wrote:
[quote]Herbert Newman wrote:
On Fri, 24 Oct 2008 20:43:59 +0100 John Jones wrote:

[...]

Did you ever seek professional help?

Herb

I should be grateful, you know. Herbet has pushed my post back to the
top of the pile of new posts. And to show my gratitude I think that it
deserves a reply.
[/quote]
Yes, as I was saying, I am really grateful. Not just grateful, but more
really grateful. I will fulfill my obligations.

John Jones · Guest

John Jones wrote:
[quote]John Jones wrote:
Herbert Newman wrote:
On Fri, 24 Oct 2008 20:43:59 +0100 John Jones wrote:

[...]

Did you ever seek professional help?

Herb

I should be grateful, you know. Herbet has pushed my post back to the
top of the pile of new posts. And to show my gratitude I think that it
deserves a reply.

Yes, as I was saying, I am really grateful. Not just grateful, but more
really grateful. I will fulfill my obligations.
[/quote]
Hi. I>m still really gratefull, at least until I need to get a beer.
This one>s running low. And I think it>s time for a big gulp and then go
and watch Takeshi>s castle. I have nits.

John Jones · Guest

John Jones wrote:
[quote]John Jones wrote:
John Jones wrote:
Herbert Newman wrote:
On Fri, 24 Oct 2008 20:43:59 +0100 John Jones wrote:

[...]

Did you ever seek professional help?

Herb

I should be grateful, you know. Herbet has pushed my post back to the
top of the pile of new posts. And to show my gratitude I think that
it deserves a reply.

Yes, as I was saying, I am really grateful. Not just grateful, but
more really grateful. I will fulfill my obligations.

Hi. I>m still really gratefull, at least until I need to get a beer.
This one>s running low. And I think it>s time for a big gulp and then go
and watch Takeshi>s castle. I have nits.
[/quote]
Did I say that?
Anyway, the buggers can come and tip me upside down but they>re not
having my bush. Remember, always, to keep a close on your bush. You
never know when someone will nick it or piss on the bloody thing.

So, Use BRILLO.
Only BRILLO outshines the sun.
That is why on BRILLO DAY we carry umbrella>s.
Lest our underpants outshine the sun. You knew it was coming.

loco · Guest

On Oct 24, 9:43 pm, John Jones <jonescard...@aol.com> wrote:
[quote]First a definition:
A 'disjunction' "A V B " read as "A or B " is false if both A and B are
false. In all other cases it is true.

The problem that arose with the connective 'and' also arises with a
disjunction.

Simply, for both disjunction and conjunction, whatever the truth values
of A and B ARE (plural case), the nature of the third element that IS
(singular case) both A and B is underdetermined whether or not that
element is true or false.

The third, unspecified element in conjunction and disjunction can be
seen in implicit form in the diagrams used to teach logical conjunction
and disjunction. Thus we have the Venn overlap and the gate of the logic
gate.

I have to put this as a challenge. What is the nature of the object that
IS 'A and B' in a conjunction or disjunction of the elements 'A' and 'B'?
[/quote]
not so sure whether I get you, but lets try. The "element" that is
both A and B" does,
without further defining what precisely the AND in "both A and B"
means, only make sense when A and B
are identical, which reduces conjunction and disjunction to (A and A)
and (A or A), both of which evaluate to
the truth value of A, which is nowhere undefined.

You might want to clarify the "both A and B", especially the way which
you want the "and"
understood. Imho it does not make terribly much sense as a logical
operator and only blur
things when used colloquially.

Mitch Harris · Guest

On Oct 24, 3:43 pm, John Jones <jonescard...@aol.com> wrote:
[quote]First a definition:
A 'disjunction' "A V B " read as "A or B " is false if both A and B are
false. In all other cases it is true.

The problem that arose with the connective 'and' also arises with a
disjunction.
[/quote]
Can you say what the problem is?

[quote]Simply, for both disjunction and conjunction, whatever the truth values
of A and B ARE (plural case), the nature of the third element that IS
(singular case) both A and B is underdetermined whether or not that
element is true or false.
[/quote]
how is it underdetermined? both 'and' and 'or' are total boolean
functions over two variables. That seems pretty exactly determined.

[quote]The third, unspecified element in conjunction and disjunction can be
seen in implicit form in the diagrams used to teach logical conjunction
and disjunction. Thus we have the Venn overlap and the gate of the logic
gate.
[/quote]
OK. So where>s the problem?

[quote]I have to put this as a challenge. What is the nature of the object that
IS 'A and B' in a conjunction or disjunction of the elements 'A' and 'B'?
[/quote]
What is the challenge? Determining the 'nature' of a logical
connective? For you, I think it>ll suffice to look at the truth
tables.

Mitch

John Jones · Guest

loco wrote:
[quote]On Oct 24, 9:43 pm, John Jones <jonescard...@aol.com> wrote:
First a definition:
A 'disjunction' "A V B " read as "A or B " is false if both A and B are
false. In all other cases it is true.

The problem that arose with the connective 'and' also arises with a
disjunction.

Simply, for both disjunction and conjunction, whatever the truth values
of A and B ARE (plural case), the nature of the third element that IS
(singular case) both A and B is underdetermined whether or not that
element is true or false.

The third, unspecified element in conjunction and disjunction can be
seen in implicit form in the diagrams used to teach logical conjunction
and disjunction. Thus we have the Venn overlap and the gate of the logic
gate.

I have to put this as a challenge. What is the nature of the object that
IS 'A and B' in a conjunction or disjunction of the elements 'A' and 'B'?

not so sure whether I get you, but lets try. The "element" that is
both A and B" does,
without further defining what precisely the AND in "both A and B"
means, only make sense when A and B
are identical, which reduces conjunction and disjunction to (A and A)
and (A or A), both of which evaluate to
the truth value of A, which is nowhere undefined.
[/quote]
I don>t think identity is involved. I>m asking if A is true, and B is
true, then what is "'A and B' is true"?

The problem is that 'A and B' can only be a valid term or sign if 'and'
is defined. But 'and' is not defined. So, how can an assertion be made
to the effect that "'A and B' is true/false", if 'A and B' is not
adequately defined (underdetermined)?

[quote]You might want to clarify the "both A and B", especially the way which
you want the "and"
understood.
[/quote]
How is 'and' understood? That is the question. 'And' is not defined or
described in logic. And its operations are for that reason,
unintelligible; what is the object A "and" B?

John Jones · Guest

Mitch Harris wrote:
[quote]On Oct 24, 3:43 pm, John Jones <jonescard...@aol.com> wrote:
First a definition:
A 'disjunction' "A V B " read as "A or B " is false if both A and B are
false. In all other cases it is true.

The problem that arose with the connective 'and' also arises with a
disjunction.

Can you say what the problem is?

Simply, for both disjunction and conjunction, whatever the truth values
of A and B ARE (plural case), the nature of the third element that IS
(singular case) both A and B is underdetermined whether or not that
element is true or false.

how is it underdetermined? both 'and' and 'or' are total boolean
functions over two variables. That seems pretty exactly determined.

The third, unspecified element in conjunction and disjunction can be
seen in implicit form in the diagrams used to teach logical conjunction
and disjunction. Thus we have the Venn overlap and the gate of the logic
gate.

OK. So where>s the problem?

I have to put this as a challenge. What is the nature of the object that
IS 'A and B' in a conjunction or disjunction of the elements 'A' and 'B'?

What is the challenge? Determining the 'nature' of a logical
connective? For you, I think it>ll suffice to look at the truth
tables.

Mitch
[/quote]

We can>t claim or assert "A and B" just on the basis that
1) we gave "A and B" a truth value,
2) "A and B" is asserted when "A" and "B" are asserted.

In 1) "A and B" is underdetermined - we don>t know, or haven>t been
told, how "A and B" has been brought together and how it differs
qualitatively and quantitatively from A and B prior to their conjunction.

In 2) "A and B" means "A" and "B" because "A and B" is fully determined
by the assertion "A" and "B".

So in 2) a conjunction is no more than a logically insignificant
translation. Also, 2) assumes that truths can be totalised, or assembled
in truth tables. Truth tables are of no value when the objecthood or
descriptions of their elements is in doubt.

Jan Burse · Guest

John Jones schrieb:

[quote]So in 2) a conjunction is no more than a logically insignificant
translation. Also, 2) assumes that truths can be totalised, or assembled
in truth tables. Truth tables are of no value when the objecthood or
descriptions of their elements is in doubt.
[/quote]
Ernst Specker constructed a paradox out of that.
He invented the operator |, which stands for
lets say "comensurable". And then a and b is only
defined when a|b holds.

Out of that it can be shown that the leibniz equality
(a and b) and (c and d) = (a and c) and (b and d)
does not necessarely hold. There is also a physical
interpretation of |.

Its all quite fun.

Bye

Mitch Harris · Guest

On Oct 24, 3:43 pm, John Jones <jonescard...@aol.com> wrote:
[quote]First a definition:
A 'disjunction' "A V B " read as "A or B " is false if both A and B are
false. In all other cases it is true.

The problem that arose with the connective 'and' also arises with a
disjunction.

Simply, for both disjunction and conjunction, whatever the truth values
of A and B ARE (plural case), the nature of the third element that IS
(singular case) both A and B is underdetermined whether or not that
element is true or false.
[/quote]
How are the total boolean functions for 'and' and 'or'
underdetermined? All the output values are specified for all possible
inputs. That>s pretty determined to me.

[quote]The third, unspecified element in conjunction and disjunction can be
seen in implicit form in the diagrams used to teach logical conjunction
and disjunction. Thus we have the Venn overlap and the gate of the logic
gate.

I have to put this as a challenge. What is the nature of the object that
IS 'A and B' in a conjunction or disjunction of the elements 'A' and 'B'?
[/quote]
What is the nature of just plain old 'A'? What does that question
mean? Well, whatever the answer I highly suspect it is the same answer
as for 'A and B'?

So you>re really not complaining about anything in particular about
'and' yet (as opposed to 'or'). You>re troubled by something about
connectives in general. Most people>s troubles are pretty much
overcome by considering truth tables or the axioms and inference rules
of the operators. Can you elaborate what else is the trouble?

Mitch

herbzet · Guest

herbzet wrote:

[quote]=================================
I>d just like to add that you might, or might not, want to distinguish
a definition of what 'and' "is" from a description of the circumstances
in which 'A and B' is true. Maybe one will serve for the other?
[/quote]
My little foray into the philosophy of the essences of things
in news:48E595EF.D7C9452A@gmail.com might have some bearing
here also.

I wrote:

Look, we don>t know what anything *is*, we just can describe its
relation to other things. A man is made of molecules, which are
made of atoms, which have protons, which are made of quarks.
What>s a quark? It>s not made of wool, or plastic, or wood.
It>s, finally, just its behaviour. Same with electrons and
other leptons. We don>t know what they "are", we just describe
their behavior with regard to other leptons, and to other sorts of
things, like quarks.

All we can say about "successor" is how things behave in relation
to other things when they have a successor or when they are a
successor etc. The description of the behaviours are the properties
of "successor" and constitute the definition of "successor".

Similarly for 'and'. We don>t define it; we give some axioms
for using it, and away we go. Some things must be accepted as
given just to kickstart the whole enterprise.

--
hz

herbzet · Guest

Herbert Newman wrote:
[quote]schrieb herbzet:

I have to put this as a challenge. What is the nature of the object that
IS 'A and B' in a conjunction or disjunction of the elements 'A' and 'B'?

If A and B are propositions, then the conjunction 'A and B' is a
proposition. A compound proposition.

I>d prefer to say: If A and B are sentences, then 'A and B' and 'A or B'
are sentences too. [I>m using the Quinean corner-quotes here.]

For example, consider the two sentences (in the English language)

John Jones is a crank.
and
John Jones is a schizophrenic.

Clearly the "resulting object"

John Jones is a crank or John Jones is a schizophrenic.

is a sentence (in the English language) again.
[/quote]
That is unquestionably true.

[quote](Concerning its "nature" I>d
say a sentence is a sentence is a sentence.)

Actually, that>s the _reason_ why we call "and" and "or" _connectives_ in
logic.
[/quote]
Yes, sentences have a reassuringingly physical existence, as opposed
to statements or propositions.

--
hz

Ross A. Finlayson · Guest

Hi,

I think this is interesting this description, even relevant:

http://www.jfsowa.com/ontology/toplevel.htm

Thanks,

Ross F.


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