How do we approach a new proposition?

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Og3
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How do we approach a new proposition?

Post by Og3 » Thu Sep 27, 2018 9:21 am

I ask as a precursor to an examination of the evaluation of new ideas.

I once was a Kripkean Dogmatist. I didn't know that I was; I was a child and didn't yet know words of those calibers. It is only in retrospect that I can admit to Kripkean Dogmatism. You see, I believed that Ford was the only good maker of automobiles, and all others were junk. The key aspect of this -- the thing that made my dogmatism Kripkean -- was that I accepted any evidence, however weak, if it favored my belief, and rejected any evidence, however strong, if it opposed my belief. When Parnelli Jones won at Laguna Seca in a Mustang, my beliefs were PROVEN! but when other races were won by Chevies, those races were meaningless, pointless, and had no bearing on the question. Kripkean Dogmatism at its finest.

Clearly, such a belief and such a dogmatism are wrong. I have owned many fine autos of various makes, and I would now hesitate to declare any of them bad A Priori. I still have a subjective preference for Fords, but I no longer believe them to be objectively superior. Also, I no longer judge evidence by whether or not it agrees with me. I have become amenable to persuasion.

Now, suppose that someone comes to me with a video showing an engine that runs on magnets. I know that magnets do not contain energy -- they exert force based upon their location within a field, or if you favor relativity, they alter spacetime. But in order for them to do work, first work must be done to them. But I will watch the video, nonetheless, because I am amenable to reason. And then I'll look for the flaw in the video; the thing left off camera or hidden on the other side of the so-called magnet motor.

To date, I've never seen a magnet motor that worked without some skulduggery behind the scenes. If I did, I would investigate further. It is not inconceivable that I might even become convinced by it, after careful, sound, and scientific testing. But I sincerely doubt it.

Suppose that someone were to present the proposition that "light bulbs," instead of emitting a visible radiation, instead suck up darkness. Well, that is a theory that is both explanatory and predictive, so I would consider both the visible radiation theory and the dark-sucking theory until I reached a conclusion that one or the other better fit the known facts.

I try to use, as a guide, the principle that I may not dismiss a proposition until I know what's wrong with it. That is, I can't just tell you that dark-sucking theory is stupid; I have to be able to say that it violates a known physical principle. Until I can do that, I don't have to accept dark-sucking theory; I just can't reject it.

This principle -- and sometimes I do better with it than at other times -- has led me to study formal logic. I try to fit propositions into syllogisms so that I can apply rules to them, and see if they fit the rules.

So, how do the rest of you consider a new proposition? What are your criteria for acceptance or rejection?
EGO TE ABSOLVO, and there's nothing you can do about it.

Og3
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Re: How do we approach a new proposition?

Post by Og3 » Thu Sep 27, 2018 7:55 pm

So, any proposition -- any statement about something -- has one of four basic forms:

All Subject are Predicate -- SAP (A from Affirmo, I Affirm)
Some Subject are Predicate -- SIP (I from affIrmo, I affIrm)
All subject are NOT Predicate -- SEP (E from nEgo, I dEny)
Some Subject are NOT Predicate -- SOP (O from negO, I deny)

Strong Affirmo (SAP) is contradicted by weak Nego (SOP) (Contradictories)
Strong Nego (SEP) is contradicted by weak Affirmo (SIP) (Contradictories)
Strong Affirmo and Strong Nego are "Contraries" because they are mutually exclusive and categorical.
Weak Affirmo and Weak Nego are "Sub-contraries" because they are not mutually exclusive.
Strong and Weak Affirmo, or Strong and Weak Nego, are "subalterns"

These terms come from Alexander Wolf's A Textbook of Logic.
EGO TE ABSOLVO, and there's nothing you can do about it.

Humanguy
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Re: How do we approach a new proposition?

Post by Humanguy » Fri Sep 28, 2018 12:32 am

Is there going to be a test on this?

Og3
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Re: How do we approach a new proposition?

Post by Og3 » Fri Sep 28, 2018 6:26 am

Life is a test on this.
EGO TE ABSOLVO, and there's nothing you can do about it.

Og3
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Re: How do we approach a new proposition?

Post by Og3 » Fri Sep 28, 2018 7:26 am

So if I say "My car is red" I am proposing to you that:

1. Some cars are red. Some Subject (cars) are Predicate (red). (SIP)
2. My car belongs to that class of cars that are red.

The sub-contrary to "some cars are red" is that "some cares are not red." (SOP). These are not contradictories -- they can both be true. In fact, if some cars are red, that implies that some cars are not red, or else we would have said "All cars are red." But "All cars are red" also does not contradict that "Some cars are red" -- these statements are called "Subalterns" -- that won't be on the test.

The contradictory of "Some cars are red" -- that is, the statement that can't also be true -- is that "No Cars are red." (or all cars are not red).

Please note that we are just considering the form at this point. We are not assigning a truth value to the statements.

Now, we can also convert two of these SAP/SIP/SEP/SOP forms to a "General Premise," which is something we will talk about later. A General Premise has the form, "If X, then Y." So....

If we proposed that "All cars are red" we would be proposing that "If it is a car, then it is red." (SAP)
If we proposed that "No cars are red" we would be proposing that "If it is red, then it is not a car." (SEP)

Have I lost anyone thus far?
EGO TE ABSOLVO, and there's nothing you can do about it.

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SEG
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Re: How do we approach a new proposition?

Post by SEG » Fri Sep 28, 2018 10:31 am

Og3 wrote:
Fri Sep 28, 2018 7:26 am
So if I say "My car is red" I am proposing to you that:

1. Some cars are red. Some Subject (cars) are Predicate (red). (SIP)
2. My car belongs to that class of cars that are red.

The sub-contrary to "some cars are red" is that "some cares are not red." (SOP). These are not contradictories -- they can both be true. In fact, if some cars are red, that implies that some cars are not red, or else we would have said "All cars are red." But "All cars are red" also does not contradict that "Some cars are red" -- these statements are called "Subalterns" -- that won't be on the test.

The contradictory of "Some cars are red" -- that is, the statement that can't also be true -- is that "No Cars are red." (or all cars are not red).

Please note that we are just considering the form at this point. We are not assigning a truth value to the statements.

Now, we can also convert two of these SAP/SIP/SEP/SOP forms to a "General Premise," which is something we will talk about later. A General Premise has the form, "If X, then Y." So....

If we proposed that "All cars are red" we would be proposing that "If it is a car, then it is red." (SAP)
If we proposed that "No cars are red" we would be proposing that "If it is red, then it is not a car." (SEP)

Have I lost anyone thus far?
If we proposed that "SEG cars are red" we would be proposing that "If it is red, then it is SEG's car." (SEG)
Premise One: If a compassionate God exists, then he would do things just as a compassionate person would.
Premise Two: God doesn't do things as a compassionate person would.
Conclusion: Therefore, a compassionate God does not exist.

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Moonwood the Hare
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Re: How do we approach a new proposition?

Post by Moonwood the Hare » Fri Sep 28, 2018 8:54 pm

Og3 wrote:
Fri Sep 28, 2018 7:26 am
The sub-contrary to "some cars are red" is that "some cares are not red." (SOP). These are not contradictories -- they can both be true. In fact, if some cars are red, that implies that some cars are not red, or else we would have said "All cars are red." But "All cars are red" also does not contradict that "Some cars are red" -- these statements are called "Subalterns" -- that won't be on the test.
There may be a mistake here. In most common speech some cars are red would imply some cars are not red, but if you are using 'some' and 'all' as verbal approximations to the existential and universal quantifiers in propositional calculus ("∃" and "∀") then there would be no such implication as the existential quantifier only implies that at least one exists. Which is to say ∃x(car(x)ɅisRED(x)) does not imply some cars are not red. I tried to write the second part in calculus but it defeated me.

As an aside my daughter who took a degree in Maths once told me that when Frege constructed the logic he based his theory of number on he did not use any existential quantifiers at all. So the nearest he could get to 'some' was 'not all are not'. So 'some cars are red' would come out as 'not all cars are not red'. But there is at least one state of affairs where the two are not equivalent. 'Not all cars are not red' could be true if there are no cars, 'some cars are red' could not. Popper pulls a similar stunt when he says 'All swans are non-white' and 'all swans are white' could both be true if there are no swans.

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SEG
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Re: How do we approach a new proposition?

Post by SEG » Fri Sep 28, 2018 10:37 pm

Humanguy wrote:
Fri Sep 28, 2018 12:32 am
Is there going to be a test on this?
Hahahar!
Premise One: If a compassionate God exists, then he would do things just as a compassionate person would.
Premise Two: God doesn't do things as a compassionate person would.
Conclusion: Therefore, a compassionate God does not exist.

Og3
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Re: How do we approach a new proposition?

Post by Og3 » Sat Sep 29, 2018 7:47 am

SEG wrote:
Fri Sep 28, 2018 10:31 am
Og3 wrote:
Fri Sep 28, 2018 7:26 am
So if I say "My car is red" I am proposing to you that:

1. Some cars are red. Some Subject (cars) are Predicate (red). (SIP)
2. My car belongs to that class of cars that are red.

The sub-contrary to "some cars are red" is that "some cares are not red." (SOP). These are not contradictories -- they can both be true. In fact, if some cars are red, that implies that some cars are not red, or else we would have said "All cars are red." But "All cars are red" also does not contradict that "Some cars are red" -- these statements are called "Subalterns" -- that won't be on the test.

The contradictory of "Some cars are red" -- that is, the statement that can't also be true -- is that "No Cars are red." (or all cars are not red).

Please note that we are just considering the form at this point. We are not assigning a truth value to the statements.

Now, we can also convert two of these SAP/SIP/SEP/SOP forms to a "General Premise," which is something we will talk about later. A General Premise has the form, "If X, then Y." So....

If we proposed that "All cars are red" we would be proposing that "If it is a car, then it is red." (SAP)
If we proposed that "No cars are red" we would be proposing that "If it is red, then it is not a car." (SEP)

Have I lost anyone thus far?

If we proposed that "SEG cars are red" we would be proposing that "If it is red, then it is SEG's car." (SEG)
Actually SEG would come from nEgo (I deny) so we would be saying that no Subject are Gredicate. And I think Gred was the Weasley who died in the last book of the Harry Potter series. So that won't work.
EGO TE ABSOLVO, and there's nothing you can do about it.

Og3
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Re: How do we approach a new proposition?

Post by Og3 » Sat Sep 29, 2018 8:03 am

Moonwood the Hare wrote:
Fri Sep 28, 2018 8:54 pm
Og3 wrote:
Fri Sep 28, 2018 7:26 am
The sub-contrary to "some cars are red" is that "some cares are not red." (SOP). These are not contradictories -- they can both be true. In fact, if some cars are red, that implies that some cars are not red, or else we would have said "All cars are red." But "All cars are red" also does not contradict that "Some cars are red" -- these statements are called "Subalterns" -- that won't be on the test.
There may be a mistake here. In most common speech some cars are red would imply some cars are not red, but if you are using 'some' and 'all' as verbal approximations to the existential and universal quantifiers in propositional calculus ("∃" and "∀") then there would be no such implication as the existential quantifier only implies that at least one exists. Which is to say ∃x(car(x)ɅisRED(x)) does not imply some cars are not red. I tried to write the second part in calculus but it defeated me.

As an aside my daughter who took a degree in Maths once told me that when Frege constructed the logic he based his theory of number on he did not use any existential quantifiers at all. So the nearest he could get to 'some' was 'not all are not'. So 'some cars are red' would come out as 'not all cars are not red'. But there is at least one state of affairs where the two are not equivalent. 'Not all cars are not red' could be true if there are no cars, 'some cars are red' could not. Popper pulls a similar stunt when he says 'All swans are non-white' and 'all swans are white' could both be true if there are no swans.
Worthy points. In common speech, we would imply "Some cars are not red" when we state that "some cars are red," but we do not imply in formal logic.

My point was to show that only SEP contradicts SIP. SAP or SOP could either be true if SIP is true. But SAP and SOP could not both be true, because they are contradictories. Likewise SEP and SIP cannot both be true. still, that's a very good point.

Now, your point on Popper and swans leads us to another important point, which is that we need to know what words mean... We need to define things. If by "Car" I mean "invisible pink elephant" then it cannot be true that some cars are red or that some cars are not red, because invisible pink elephants do not exist. How do I know that invisible pink elephants do not exist? Because if an elephant is pink, then he reflects faint light in the 620nm to 750nm band, and if he is invisible, then he reflects no light at all. This is a contradiction in terms, thus no such elephant can exist... But we're getting ahead of ourselves.

To be a bit more realistic -- is a truck a car? Well, if we say that 500 cars drove past a stop sign without stopping, we mean "cars and trucks" in that context. And if we say, "all cars have trunks" then we have excluded trucks from our definition of cars.

Unfortunately, we have included elephants and soldiers. Thus the point is made: To use words logically we must have a clear and UNAMBIGUOUS understanding of what a particular word means.
EGO TE ABSOLVO, and there's nothing you can do about it.

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