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Tahnan
Posted: Tue May 31, 2005 7:40 am    Post subject: 1

Dan wrote:
You can't phrase anything in the English language with logic.

Horsehockey. I refer the reader to Richard Montague's "The Proper Treatment of Quantifiers in English" and the 30-odd years of research that followed.

Incidentally, Samadhi, your teacher is an i...no, no, I think your teacher is using words in ways that all of us are wholly unaccustomed. And I'm not really sure what point he's making with them.
CB
Posted: Mon Apr 25, 2005 6:41 pm    Post subject: 0

I might be utterly wrong here, but why can't "big and strong" represent a predicate "as is"? Does it have to be atomic?

In fact, i don't care if there is no thing that is "electronic and rich", the concept is still valid in my mind. In terms of sets, the "electronic" and "rich" sets define (TTBOMK) four other sets, one of which is their intersection. And since i don't see why we would need a new word for it, i would use the conjuction of the two properties.

From this point of view, the sentence is "x is P". No implicitness here...

New idea: If the sentence were "The bald skinny guy over there is a teacher", i would have no hesitation to put it into the same "x is P" category, although the 'x' would not be atomic. Or would it?
extro...
Posted: Sat Apr 23, 2005 2:46 am    Post subject: -1

Dan wrote:
The sentence structure has a piece of implied information in it that is not immediately obvious from simply reading/saying the sentence "Tom is big and strong".

It must not be obvious, because I can't see it at all. I mean, I can see it implies Tom is big, and that it implies Tom is strong, but any 4 year old would grasp that without thinking. That much is obvious immediately, if not sooner. So what am I missing?
Dan
Posted: Sat Apr 23, 2005 12:38 am    Post subject: -2

The sentence structure has a piece of implied information in it that is not immediately obvious from simply reading/saying the sentence "Tom is big and strong". I find that piece of structure interesting, and though it might be simple, it is not necessarily obvious, so I don't think it's inane.

And is it subliminal? It might actually be so, depending on what you believe about one's native language and how the brain works (I'm not proposing I beleive this, I'm just saying one could make a case for it).
Posted: Sat Apr 23, 2005 12:05 am    Post subject: -3

The only thing I can think of that is not inane, is if you're saying it like subliminal man.
Bicho the Inhaler
Posted: Fri Apr 22, 2005 11:39 pm    Post subject: -4

extro, that's what I think, as well. There are different ways to define "implicit", some of which are interesting and relevant, and others of which are not worthy of more than a mention, if that.
Dan wrote:
Ah, I see now that this is where what Bicho was talking about comes in, but I would hardly call this syntactic property "superficial" or "inane". It is a part of our language's deep-structure syntax.
What is not superficial about the distinction between "Tom is big" and "Tom is strong" as implied by the sentence "Tom is big and strong"? And if it isn't inane, there must be something interesting to say about it.
extro...
Posted: Wed Apr 20, 2005 2:35 am    Post subject: -5

This all seems to be about various meanings of the word "implicit". One is very common usage, and very relevant to a logic and critical thinking course: Something that is left unsaid and unmentioned, but can be understood to be an assumption or an implication. The other is a usage that we're not even sure is real (i.e., is the term really used that way?) - a sort of syntactic thing that describes, in this case, the difference between parts of two sentences with different surface structure, but identical deep structure. This latter notion of an "implicit" statement is something that requires no more critical thinking than what is done automatically by an average five year old.

Actually, you could argue that in the sentence "Tom is big", it is implicit that "Tom" means Tom, "big" means big, and "is" means is. It is implicit. The sentence doesn't explicitly state that the words have their usual meanings. It's about as meaningful an avenue of discussion, IMO.
Dan
Posted: Wed Apr 20, 2005 2:29 am    Post subject: -6

The stucture of the sentence dictates which statement is implicit. It's not that one is explicit and the other not. In different positions they are different things.
Posted: Wed Apr 20, 2005 2:03 am    Post subject: -7

Yes, but I hardly think that qualifies one as exlicit and the other not.
Dan
Posted: Wed Apr 20, 2005 1:46 am    Post subject: -8

I was serious though Sam. "John is big and strong" and "John is strong and big" have the same "meaning" (if I were so arrogant as to claim to know what that is). But they obviously are not the same sentence, they have different structure.
Posted: Tue Apr 19, 2005 5:35 pm    Post subject: -9

sheesh. I get no respect.
GH
Posted: Tue Apr 19, 2005 3:52 pm    Post subject: -10

The first 5 words of the thread wrote:
My "Logic and Critical Thinking" teacher

The implication is that you can't count to 6.
Posted: Tue Apr 19, 2005 5:43 am    Post subject: -11

Dan wrote:
It doesn't. "John is strong and big" does.
Bah. I hope you know what I meant.
Dan wrote:
What class is this for anyway Sam?

The first 5 words of the thread wrote:
My "Logic and Critical Thinking" teacher

The answer to your question is a good example of an implicit statement, unlike the one in the opening post, IMO.
Dan
Posted: Tue Apr 19, 2005 4:40 am    Post subject: -12

Ah, I see now that this is where what Bicho was talking about comes in, but I would hardly call this syntactic property "superficial" or "inane". It is a part of our language's deep-structure syntax. Though I could not say off the top of my head if this could be technically called an "implicit" subject, I think it makes sense that it would be called so. But it may just be an "unstated premise" or "assumed/unstated subject". This sort of distinction also depends on who's teaching you linguistics. :p

What class is this for anyway Sam?
Dan
Posted: Tue Apr 19, 2005 4:24 am    Post subject: -13

It doesn't. "John is strong and big" does.
Posted: Tue Apr 19, 2005 3:49 am    Post subject: -14

I have no training with the formulas you're using. When I said "typical" I meant typically what I or any other layman might see, as opposed to the "typical" esoteric usage. Sorry for the ambiguous term.

My main point is that I really don't see how saying "John is big and strong" is explictly saying "John is strong" but only implying that "John is big"
Dan
Posted: Mon Apr 18, 2005 11:41 pm    Post subject: -15

If I had to pick one thing I didn't like about the new boards...:p
Guest
Posted: Mon Apr 18, 2005 11:40 pm    Post subject: -16

Bicho the Inhaler wrote:
Dan wrote:
How would you represent that in logic? Cause I think your teacher probably has the "Ba^Sa" business in mind. How do you represent the idea that A has all the properties in that set {B, C}?
What's wrong with the way he has it? I think there might be a fundamental difference in the ways we're thinking about it.

That's possible. But Sam mentioned logic, so I assumed that he was taking the approach of logic. I tried to fit the sentence into logic in a couple different ways.

Bicho wrote:
Quote:
I think my basic question is: How do you logically represent the "having" in your statement "A has the properties (B,C)"? I assume it is either part of the variables B and C (the properties) or part of other type of variable A (the subject), or are you proposing an operator for the verb "to have" (I'm not familiar with any)?
You seem to be imposing a restricted formalism on this problem that wasn't there to begin with. I don't know if Samadhi's class is about formal logic. In any case, it is not the only way to think about logic. Any formalism you come up with is guaranteed (mathematically) to be incomplete anyway. There will always be situations that require insights exterior to the formalism.

Yes, formalism is incomplete. BU ti thought itwas the approach Sam was taking to the problem, so I went with it. What other ways to think about logic are applicable here?

Bicho wrote:
Quote:
My argument is that when the sentence "Tom is big and strong" is put in a logical form, it reveals the implicit statement the teacher was talking about.
Maybe, but does it reveal the difference between the two statements "Tom is big" and "Tom is strong" as conveyed by that sentence? The main point made was not simply that there is an implicit statement lurking in there, but that of two statements of apparently equal status, one is somehow explicit while the other is implicit.
[/quote]

The two are apparently of equal status when represented in logic. In English, there is something implicit. WHY it is implicit and what the nature of that implicit statement is is a question for linguistics (my OTHER minor). I'm not about to draw sentence trees right now though. Study for test time. (I've seriously spent more time thinking about logic in this thread than I have studying for my logic test TOMORROW :p).
Posted: Mon Apr 18, 2005 6:47 pm    Post subject: -17

Quote:
But the main thing that bothered me was Sam's reference to "typical logical formulas", without giving any valid formulas that could represent the sentence. Sorry. :p
Bad phrasing. I was trying to making it clear that I was saying that from a layman's perspective. Most logic I know comes from math.
Posted: Mon Apr 18, 2005 6:44 pm    Post subject: -18

MatthewV wrote:
*He insists on not using a comma before "and" in a list.

Lynch, Guide to Grammar and Style wrote:
In most house styles, the comma is preferred before the last item in a list: "the first, second, and third chapters." (This is known as the serial comma or the Oxford comma.) Leaving it out — "the first, second and third chapters" — is a habit picked up from journalism. While it saves a teensy bit of space and effort, omitting the final comma runs the risk of suggesting the last two items (in the example above, the second and third chapters) are some sort of special pair. A famous (and perhaps apocryphal?) dedication makes the danger clear: "To my parents, Ayn Rand and God."

And that is why I try to include the comma in every list I make now.

Yes, I also mentioned the difficult when listed pairs in lists. Such as: "I watched Futurama, The Family Guy, Bulls and bears." Bulls and Bears is a TV show so...did I watch bulls and watch bears or did I watch bulls and bears?
Bicho the Inhaler
Posted: Mon Apr 18, 2005 6:23 pm    Post subject: -19

Dan wrote:
How would you represent that in logic? Cause I think your teacher probably has the "Ba^Sa" business in mind. How do you represent the idea that A has all the properties in that set {B, C}?
What's wrong with the way he has it? I think there might be a fundamental difference in the ways we're thinking about it.
Quote:
I think my basic question is: How do you logically represent the "having" in your statement "A has the properties (B,C)"? I assume it is either part of the variables B and C (the properties) or part of other type of variable A (the subject), or are you proposing an operator for the verb "to have" (I'm not familiar with any)?
You seem to be imposing a restricted formalism on this problem that wasn't there to begin with. I don't know if Samadhi's class is about formal logic. In any case, it is not the only way to think about logic. Any formalism you come up with is guaranteed (mathematically) to be incomplete anyway. There will always be situations that require insights exterior to the formalism.
Quote:
My argument is that when the sentence "Tom is big and strong" is put in a logical form, it reveals the implicit statement the teacher was talking about.
Maybe, but does it reveal the difference between the two statements "Tom is big" and "Tom is strong" as conveyed by that sentence? The main point made was not simply that there is an implicit statement lurking in there, but that of two statements of apparently equal status, one is somehow explicit while the other is implicit.
Dan
Posted: Mon Apr 18, 2005 3:43 pm    Post subject: -20

Antrax wrote:
In any case, you could form it like this: Tom->(Big^Strong). I'm just not sure what your argument is - you can phrase anything in the English language with logic.

You can't phrase anything in the English language with logic. Logic does it's best, but does not suffice in some areas. But that's besides the point.

Tom->(Big^Strong) doesn't mean anything to me. It would mean "If Tom, then big and strong" or "Tom implies big and strong".

For sentences of the form a->(b^c), the variables a, b, and c need to represent statements that have a truth-value. "Tom" does not have a truth value, and neither do "big" and "strong".

My argument is that when the sentence "Tom is big and strong" is put in a logical form, it reveals the implicit statement the teacher was talking about.

Bicho wrote:
But the way he's doing it is particularly inane.

It may be a simple example, lacking in a whole lot of deep meaning, but that doesn't make it any less valid. There is something "implicit" going on in that sentence. The professor may not be making the best example, but it is still an implicit statement which surfaces when the sentence is put in a logical form.

But the main thing that bothered me was Sam's reference to "typical logical formulas", without giving any valid formulas that could represent the sentence. Sorry. :p
Dan
Posted: Mon Apr 18, 2005 3:31 pm    Post subject: -21

Please excuse the double post. Or my dear Aunt Sally. Whichever really.
MatthewV
Posted: Mon Apr 18, 2005 8:28 am    Post subject: -22

*He insists on not using a comma before "and" in a list.

Lynch, Guide to Grammar and Style wrote:
In most house styles, the comma is preferred before the last item in a list: "the first, second, and third chapters." (This is known as the serial comma or the Oxford comma.) Leaving it out — "the first, second and third chapters" — is a habit picked up from journalism. While it saves a teensy bit of space and effort, omitting the final comma runs the risk of suggesting the last two items (in the example above, the second and third chapters) are some sort of special pair. A famous (and perhaps apocryphal?) dedication makes the danger clear: "To my parents, Ayn Rand and God."

And that is why I try to include the comma in every list I make now.
Bicho the Inhaler
Posted: Mon Apr 18, 2005 6:29 am    Post subject: -23

Dan, you've also got me confused...what are you trying to say?

I think the problem as most people (including me) see it is that Samadhi's professor is treating implicitness as a very superficial syntactic property, as if to trivialize it, while it deserves careful attention. There's nothing logically wrong with it...implicitness and explicitness are sort of blurry concepts, and you can make the distinction at different places. But the way he's doing it is particularly inane.
Antrax
Posted: Mon Apr 18, 2005 6:04 am    Post subject: -24

Dan wrote:
It's not saying what the English sentence is saying.

A<->B^C says something to the effect of "A, if and only if B and C", or "If A then B, and If A then C". Equivalence is a two-way implication and it doesn't say at all what something "is". If you try to apply it to the sentence you get something like:
Code:

If "Tom" is true then "big and strong" is true, and If "big and strong" is true then "Tom" is true.

It doesn't make any sense to call equivelence (<->, or three horizontal lines) the same as "equaling" or meaning the same thing as "is". "<->" basically means that both statements on each side of the operator have the same truth value (whether true or false).
As opposed to "Tom iff strong" and "big", I suppose?
In any case, you could form it like this: Tom->(Big^Strong). I'm just not sure what your argument is - you can phrase anything in the English language with logic.
Posted: Mon Apr 18, 2005 5:58 am    Post subject: -25

How would you represent that in logic? Cause I think your teacher probably has the "Ba^Sa" business in mind. How do you represent the idea that A has all the properties in that set {B, C}?

I think my basic question is: How do you logically represent the "having" in your statement "A has the properties (B,C)"? I assume it is either part of the variables B and C (the properties) or part of other type of variable A (the subject), or are you proposing an operator for the verb "to have" (I'm not familiar with any)?

Another idea: B and C are members of the "set of properties of A". But how would this work into your English sentence? The only way I see it working is to say:

(in these formulas let "e" mean "exists in", cause I don't know how to make that symbol here)

B = "big"
S = "strong"
BeP^SeP where P is "the set of properties of the object Tom".

Is "BeP^SeP" the kind of interpretation you intended? "Big is a property that exists in P and Strong is a property that exists in P."

But now we have the same problem. In English, we don't have to say that "Tom has the property B and Tom has the property S". We just simply say "Tom has the properties B and S."

The question is, Is this statement valid?

BeP^SeP -> (B^S)eP

It would seem that this is valid, but I think there's a fallacy (I could just be sleepy). "B" and "S" are individual properties. Is "B^S", a conjunction, also a property? If not, it does not belong in the set of properties P. I would argue that "B^S" is not a property, because it seems odd to me to apply it to many different things.

For instance. To say "big and strong" is equivalent in "Tom is big and strong" and "Jake is big and strong" seems odd to me since the entire phrase "big and strong" is being treated as one property, one adjective, when it is in fact two. There is soemthing going on behind the scenes with the second adjective (in this case "strong"). The subject is being applied to it after the subject was already applied to the first adjective. There is somethign telling it to apply also to the second. This is the implication.

(And don't go saying "big and strong" have been mushed together by language to form one adjective. That may be true, but this has to work for all adjectives. Try treating "electronic and rich" as one adjective.)

P.S. Sorry about the rantage, I'm just legitimately trying to figure out the semantics of the problem. I really should be studying for my logic test. :-p
Posted: Mon Apr 18, 2005 4:23 am    Post subject: -26

I meant more along the lines A has the properties (B, C)
Dan
Posted: Sat Apr 16, 2005 7:44 pm    Post subject: -27

It's not saying what the English sentence is saying.

A<->B^C says something to the effect of "A, if and only if B and C", or "If A then B, and If A then C". Equivalence is a two-way implication and it doesn't say at all what something "is". If you try to apply it to the sentence you get something like:
Code:

If "Tom" is true then "big and strong" is true, and If "big and strong" is true then "Tom" is true.

It doesn't make any sense to call equivelence (<->, or three horizontal lines) the same as "equaling" or meaning the same thing as "is". "<->" basically means that both statements on each side of the operator have the same truth value (whether true or false).
Antrax
Posted: Sat Apr 16, 2005 11:52 am    Post subject: -28

What's wrong with A<->(B^C)?
Dan
Posted: Sat Apr 16, 2005 11:11 am    Post subject: -29

What "Typical logical formulas" are you talking about? Are you talking about biconditionals (equivalaence?).

If so, "A is B and C" does not mean what you want it to mean. If you are talking about a biconditional, the sentence would be formed like this "A<->B and C", or to finish the job "A<->B^C". But to say A has the equivalent truth value as "B and C" doesn't make sense.

Perhaps we should use predicate logic. Let Bx mean "x is big" and Sx mean "x is Strong". So the sentence can be represented as "Ba and Sa" ("Ba^Sa").

This would translate "literally" to "A is big and A is strong", which unfortunately supports your teacher's position. In logic it would be represented this way (I can't think of another way, at least not right now), but in English it is not so "explicit". In English we drop the second mention of A because it is implicit that we are still talking about the same subject.
Doc Borodog
Posted: Fri Apr 15, 2005 7:48 pm    Post subject: -30

He's an idiot.
Posted: Fri Apr 15, 2005 4:16 pm    Post subject: -31

I asked that, it wasn't the reason.
Jack_Ian
Posted: Fri Apr 15, 2005 11:31 am    Post subject: -32

Perhaps he was trying to say that it is implied that Tom is strong because he is big and that the phrase "big and strong" was used based purely on the observation that Tom was big.
Posted: Fri Apr 15, 2005 5:31 am    Post subject: -33

One thing I mentioned when briefly arguing with him (briefly because I don't want to take up too much time in the class) was the possibility that the second proposition is, for lack of a better word, sneakier. If you look at it in a formulaic manner then everything is equal, but that's not how the mind works. I don't know the particular fallacy, but there is a fallacy where you try to sneak in one false proposition with a true one by conflation.

He either didn't know what I was talking about or he ignored it out of hand. Either way, whatever.
Dan
Posted: Fri Apr 15, 2005 4:27 am    Post subject: -34

wordcross wrote:
Either way, what the hell is a logic teacher doing trying to use grammar to teach logic?

They are inevitably intertwined. A lot of logic is about trying to represent natural language systematically. "Using grammar to teach logic" is foolish on the basic level since simple rules of sybolic logic don't obey the rules of natural language (for instance the symbolic conditional "->"). But more advanced and tricky stuff tries ever harder to represent language. This is where the messed up shit like modal logic and counterfactuals (and all sorts of other stuff I haven't studied for next Tuesday's test yet) come in.
austinap
Posted: Fri Apr 15, 2005 2:45 am    Post subject: -35

At least I'm not the only one with an idiotic logic professor. My current one is a complete idiot. God I hate generals.
Posted: Fri Apr 15, 2005 1:42 am    Post subject: -36

Even worse today.

The three propositions of "Tom, Dick* and Harry are cool dudes" are all implicit because you have to change "are," but none of the propositions in "Tom kicked the dog, Harry kicked the cat and he kicked the bucket" are because even though the pronoun is ambiguous it doesn't need to be changed.

Meh.

*He insists on not using a comma before "and" in a list.
Courk
Posted: Thu Apr 14, 2005 9:35 pm    Post subject: -37

I could make a post repeating every point that's already been made, or I can just nod in agreement.

Posted: Thu Apr 14, 2005 4:04 pm    Post subject: -38

extropalopakettle wrote:
extropalopakettle wrote:
You're right, he's wrong.

And the implicit assumption here is that the student can ever be right, and the teacher wrong. Probably not if he has tenure.

He does. We'll see how it goes.