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Related Discussions
Beliefs v. Facts
extramedium
Alum Member
I've only come across this type of flaw a few times, but I'd like to understand the structure behind it. The explanation and example offered in the curriculum are not very clear. Is this similar to an is vs. ought flaw? Can someone offer an additional example?
Comments
Hi!
It is not the same as is to ought. The reason that is not the case is because "is" is descriptive. For example, the sky is blue. Ought is prescriptive. "Police officers ought to uphold the law." "Is" is much more universal. We know that the sky is blue, that is always going to be true. But do police officers always uphold the law? We know that they SHOULD but that doesn't necessarily mean that they do.
This is quite different from believe to fact flaws. They are often sciencey and look something like this (can't find an example at the moment, but if I do I will let you know!):
Professor X is has been studying the Kepler-22 B for 3 months. For the first time, his calculations have lead him to the conclusion that there are GRB's coming from the planet. GRB's can arise only if there is life. Therefore, we can conclude that there is definitely life on Kepler 22-B.
Is this necessarily the case? He believes that there are GRB's; this is what was borne out of his calculations. But that doesn't necessarily mean that there are GRB's. What if his calculations are off? What if Professor X is an accounting professor? There is just so much that we don't know, but the main issue is that we don't know whether or not his calculations are right. Because of this, we can't definitively conclude, on the basis of what Professor X believes, that there is life on Kepler 22-B.
Hope this helps!
@JustDoIt
Thanks. That's really difficult to see. I'm sure this will be a flaw in some of the more difficult questions. That looks like a completely legitimate argument on first read.
Maybe they should call this flaw something different. It's really hard to say what he believes here. He concludes something. I don't if he believes it or not. Seems to be the case with the original example I posted as well.
What would you say to strengthen or weaken an argument like this?
Strengthen: His results and calculations have been confirmed and verified by most of the scientific community.
Weaken: One of the various things you pointed out? He is an amateur that just started learning science yesterday. His calculations are inaccurate.
Is that right?
Think about it this way.
Premise 1) Fact: An apple has complex sugars that can break down fat. (lets pretend its a fact.)
Premise 2) You know this is an apple.
Conclusion: You know this apple has complex sugars that can break down fat.
Problem: You just may not "know" that apple has complex sugars that can break down fact. That's an assumption the stimulus makes. To weaken or strengthen this argument, you want to exploit that.
Yeah, completely agree. The shift is very very slight. We are given two premises. One of them is a fact about a phenomena. The other one is about what this Doctor knows. The argument concludes by combining the two premise that the doctor knows about the phenomena.
Well the conclusion is that "Dr. knows about that fact". But I think you are right, the name is sort of confusing for this example.
I don't think this would strengthen the argument. The conclusion is not that the Doctor is right but the Doctor "knows" that the lab detected a pulse. So even if the fact is verified by everyone, we still have to make the premise and conclusion come together in order to strengthen the argument. And the argument is the premise + conclusion, not just the premise together. So in order to strengthen by combining a fact with what a doctor knows, to conclude more about what the doctor might know about that original fact, we first have to assume the doctor knows about that fact. That's where the gap is, and a right answer choice will most likely center around that huge gap.
- It's not about his calculations being accurate vs inaccurate, his calculations can be wrong. It's about him "knowing" that an FRB will result in a pulse lasting more than a few milliseconds. That's the conclusion. The doctor "knows" not that he is correct. And the speaker concludes this from a fact that the doctor knows its an FRB and combines it with a fact about FRB. He is then concluding that the Doctor knows about that particular fact of FRB.
So in order to weaken this we simply have to say that somehow the Doctor does not know about this fact.
I hope this helps.
Hey @Sami I was actually commenting in on JustDoIt's example in my response. It was a different but similar argument. The original example doesn't talk about calculations. Could probably use your help on my routine thread as well though. Thanks!
https://7sage.com/discussion/#/discussion/10582/help-me-design-a-routine
@Sami This seems like a valid argument. Apple->complex sugars. You meet the sufficient in P2. How does the conclusion not follow?
Is it because of the word "know?" If it were just "this is an apple, this apple" in P2 and the conclusion, would that be valid?
Lol I worked hard on writing all that too!
.
Yeah, sure let me take a look.
Yes! Exactly! its because the noun in our conclusion is not "Apple". It's "You knowing". That's the jump.
This would be a valid argument if the conclusion said, This is an apple so it has complex sugars..... That would perfectly be a valid argument. But our conclusion is about "you knowing something". That's not guaranteed that just because there is a fact out there, you are going to know it.
Did you know, and I meant it literally, that Apple had complex sugars? No right?
Just because a fact exists, doesn't mean you can make that jump that you will now posses knowledge of it. Think about all the scientific facts that you don't know about things in your life.
Alright. Great! Thank you @Sami
My Pleasure
48-4-13 might be instructive here. Or at least the problems with drawing conclusions about actions on the basis of beliefs.
This seems good to me!
I also agree with what @Sami said. The jump is in terms of knowledge to actual facts. They are not necessarily the same thing!
Great discussion here and I don't have much to add haha everyone beat me too! If you have any other questions or there is anything I can add let me know!
This a lot like the naturalistic fallacy (NF) (is/ought). Both are modal fallacies. The NF involves deontic modality and these knowledge problems involve epistemic modality. Knowledge assertions can usually be treated the same as belief ascriptions or any of the other propositional attitudes.
In a nutshell: modality.
Thanks @BinghamtonDave @Sami
I'm going to have to look into this flaw more since I've been thinking about it. I think this is definitely one of the more interesting flaws on the test. Took a while for it to finally sink in.
@Q.E.D.
I want whatever you're on m8
Just came across an excellent example of this flaw on a really, really valuable question: PT 31 Section 2 question 21.
@extramedium My dealer is Phil O. Sofia. Try some of this sh**:
http://fitelson.org/proseminar/barcan_marcus.pdf
@BinghamtonDave that is a beautiful, glorious example.
If anyone's interested, the modal fallacy in No. 21 goes like this (BA=belief ascription):
BA(P),
P -> Q,
So BA(Q)
...ignoring the other fallacy in the problem. Again, sentences in modal contexts lose their normal logical properties. In classical (extensional) logic, you can e.g. infer B from A&B, but statements in modal (intensional) contexts lose their normal logical properties.
Of course, modal expressions have truth values and may feature unproblematically in wider extensional formulae. Here's a valid example:
BA(P) -> BA(Q),
~BA(Q),
So ~BA(P)
This is formally identical to-
P -> Q.
~Q,
So ~P
There's no interaction between modal and non-modal content there. But some modal constructions do allow operations within and between modes. Alethic modality (necessity/possibility, □/◊) is the big one. A valid example:
□(P -> Q),
◊P -> □P,
P,
So □Q
Here's an informal interpretation that might help illustrate.
Necessarily, if 12 is divisible by 6 then 12 is divisible by 3.
If it's even possible that 12 is divisible by 6 then it must be that 12 is divisible by 6.
As a matter of fact, 12 is divisible by 6.
So it must be that 12 is divisible by 3.
And, at long last, you see that words like "must," "can," "probably," "certainly," "surely," "doubtful" etc. can function as modal constructions and must be monitored (see what-a did there?).
By the way, a guy named Rudolf Carnap got the ball rolling on alethic modal logic in the 1940s by defining the necessity operator so that it was true always and only when applied to logical truths ("L-truth"). Example:
□{ [P & (P->Q)] -> Q}
I point that out bc "must" and "necessarily" often signify the logical conclusion of an argument, which is okay. Indeed, the whole idea of the necessity operator was to express the implication between premises (sufficient) and conclusion (necessary) in logical deduction, which is not the same as material implication ('->').
Anyway, I found AC (D) of No. 21 deeply interesting, as it raises an age-old question about quantifying in. Essentially this means talking about a variable inside a modal context from outside that context. It's a famous topic in the history of logic.
The typical example:
Necessarily, the number of planets is odd.
That's "the number of planets is odd" in an alethic modal context (necessity). We know the number of planets (incl. Pluto) is 9, but is the number of planets necessarily odd? Prob not. There might have been, say, 6 planets.
The problem comes with the way I refer to 9 in the modal context. To see this more clearly, notice it's true that "necessarily, Donald is Donald;" but it's false that "necessarily, the president is Donald," even though Donald is the president.
But if we rephrased the planet sentence thus:
About the number of planets (9), it's necessarily odd.
Now the way I'm referring to 9 is outside the scope of the modal operator, and the sentence is plainly true. It's a logical certainty that 9 is odd, however I refer to it.
Same situation in (D):
John believes that 4 is an even prime number.
This is a belief ascription. The modal construction "John believes that p" bars us from inferring anything from p. That is, we can't conclude from "John believes A is B" that "John believes something is B." He failed math, clearly. He might believe the first thing and not the second. As far as we're concerned, that just says "John believes *****." The words are referentially opaque, as they say.
But if we're allowed to quantify into the context "John believes..." from outside, we can rephrase:
About the number 4, John believes it is an even prime number.
And from that it's logically guaranteed that -
There is a number such that John believes it's an even prime number.
Quantifying in switches the statement from the de dicto version (whole sentence in the scope of the modal operator) to the de re version (object reference outside the modal context).
So when I see (D), I wonder Can I quantify in? Not relevant for No. 21, which deals with a straightforward de dicto fallacy, but I'm happy if my rambling has raised any interest in modality. It's clearly nice to understand from time to time.