See how logical you are... http://www.think-logically.co.uk/lt.htm (http://www.think-logically.co.uk/lt.htm)
100%
I call shenanigans on the last question!
I got a 93% got the last answer wrong but I call bullshit. The question said:
a) Water is a molecule composed of two hydrogen atoms and one oxygen atom.
b) Every observation or examination by microscope has confirmed this.
Conclusion
Therefore we can predict that every future examination of water will reveal the same chemical composition.
I answered Valid because it define water in the first statement...
Their explanation of the answer being Invalid is not consistent with the 2 statements provided...
The last one could go either way. It says "Therefore we can predict that every future examination of water will reveal the same chemical composition".
Predict is the key word IMO. Since they say predict I see how it is valid. Predictions aren't always correct.
-----------------
I answered invalid for a different reason. The 1st statement gives the molecular composition, not the chemical one...therefore the last statement doesn't make sense as they are predicting the chemical composition, based upon the molecular one.
[I'm no chemist, so I'm not sure if how I perceived the terminology is correct...so my the reasoning for my answer could be off]
Holy shit. I'm a chick and I got 100%.
A logical chick? Nah, can't be. [thumbsup]
stupid test
93%, but I can't figure out which one a missed. I'm a bit sleep deprived right now.
93% and I agree that the last one is BS.
PREDICTION. THe question is CAN you make a prediction. and you can, since water was defined. The last one is bull shit. Technically speaking, if anyone got that last one right, your all the ones who got 93%. the rest of us who got it wrong are the ones that got 100%. ;)
Heres the kicker...
"If one defines water as a property that contains two atoms of hydrogen and one atom of oxygen only...."
The first stipulation is "Water is a molecule composed of two hydrogen atoms and one oxygen atom."
The quiz' reasoning for the answer:
Answer 15.
a) Water is a molecule composed of two hydrogen atoms and one oxygen atom.
b) Every observation or examination by microscope has confirmed this.
Invalid.
Invalid but controversial in philosophical circles. If one defines water as a property that contains two atoms of hydrogen and one atom of oxygen only, then the argument above is valid. However, it is possible also that there may exist a substance that looks like water, boils as water, freezes as water, nourishes plants and life as water, and yet has a different chemical composition to what we know as water. There is nothing that could logically prevent this possibility occurring so the argument then becomes invalid.
Quote from: NAKID on January 07, 2009, 04:31:52 PM
I got a 93% got the last answer wrong but I call bullshit. The question said:
a) Water is a molecule composed of two hydrogen atoms and one oxygen atom.
b) Every observation or examination by microscope has confirmed this.
Conclusion
Therefore we can predict that every future examination of water will reveal the same chemical composition.
I answered Valid because it define water in the first statement...
Their explanation of the answer being Invalid is not consistent with the 2 statements provided...
Quote from: superjohn on January 07, 2009, 05:12:11 PM
93% and I agree that the last one is BS.
There is a difference between inductive and deductive reasoning.
The sun has always risen at sunrise.
Will the sun rise tomorrow?
No one knows!
Just because you have not observed the exception to the rule cannot mean that it does not exist.
Quote from: alfisti on January 07, 2009, 05:40:11 PM
The quiz' reasoning for the answer:
Answer 15.
a) Water is a molecule composed of two hydrogen atoms and one oxygen atom.
b) Every observation or examination by microscope has confirmed this.
Invalid.
Invalid but controversial in philosophical circles. If one defines water as a property that contains two atoms of hydrogen and one atom of oxygen only, then the argument above is valid. However, it is possible also that there may exist a substance that looks like water, boils as water, freezes as water, nourishes plants and life as water, and yet has a different chemical composition to what we know as water. There is nothing that could logically prevent this possibility occurring so the argument then becomes invalid.
This is also right. ;)
Quote from: alfisti on January 07, 2009, 05:40:11 PM
The quiz' reasoning for the answer:
Answer 15.
a) Water is a molecule composed of two hydrogen atoms and one oxygen atom.
b) Every observation or examination by microscope has confirmed this.
Invalid.
Invalid but controversial in philosophical circles. If one defines water as a property that contains two atoms of hydrogen and one atom of oxygen only, then the argument above is valid. However, it is possible also that there may exist a substance that looks like water, boils as water, freezes as water, nourishes plants and life as water, and yet has a different chemical composition to what we know as water. There is nothing that could logically prevent this possibility occurring so the argument then becomes invalid.
The problem with this explanation is that it has nothing to do with the statements or the conclusion. So what if there is another compound that does all the things that water does? The first statement defines the term "water", and that definition has nothing to do with its properties and everything to do with composition. If water is H20, then any examination of water will reveal two hydrogen atoms and one oxygen atom. The substance is not defined by its label - "water" - its label is defined by the substance's composition.
If you want some real logic fun, try taking the LSAT.
Quote from: wark on January 07, 2009, 06:07:24 PM
There is a difference between inductive and deductive reasoning.
The sun has always risen at sunrise.
Will the sun rise tomorrow?
No one knows!
Just because you have not observed the exception to the rule cannot mean that it does not exist.
Not a fair analogy in this case. You didn't DEFINE what the sun is composed of. They did in the first place, therefore, by calling it "water" at any time will still mean it is comprised of 2 H and 1 O atoms.
Another 100% chick here. ;)
Only cause you saw us complaining about the last answer!
[laugh]
Quote from: NAKID on January 07, 2009, 07:16:20 PM
Only cause you saw us complaining about the last answer!
Nah, I clicked on the link and took the test before I read the rest of the thread. :P
And I am a chemist by training.
Quote from: NAKID on January 07, 2009, 07:09:59 PM
Not a fair analogy in this case. You didn't DEFINE what the sun is composed of. They did in the first place, therefore, by calling it "water" at any time will still mean it is comprised of 2 H and 1 O atoms.
+1 here is more fuel to the fire.
THey said ducks bark. Its a stipulation, who cares if its really true or not.
so if i said
A) The sun always rises every morning
B) The sun rises tomorrow.
will the sun rise the day after tomorrow?
Yes, because the sun rises every morning, just like water is always h2o. In reality, the sun doesnt rise every morning. The earth just spins. :p
Question 15.
a) Water is a molecule composed of two hydrogen atoms and one oxygen atom.
b) Every observation or examination by microscope has confirmed this.
Conclusion
Therefore we can predict that every future examination of water will reveal the same chemical composition.
It's invalid but not for the reason they gave. Premise b) states" that every observation or examination by microscope has confirmed this." But to conclude that every future examination will reveal the same is not supported since a different future method of examination of water, such as dipping a toe into it or mixing it with scotch, might not confirm the chemical composition. Not all examinations will reveal the chemical composition.
Quote from: Johnny OrganDonor on January 07, 2009, 07:54:56 PM
Question 15.
a) Water is a molecule composed of two hydrogen atoms and one oxygen atom.
b) Every observation or examination by microscope has confirmed this.
Conclusion
Therefore we can predict that every future examination of water will reveal the same chemical composition.
It's invalid but not for the reason they gave. Premise b) states" that every observation or examination by microscope has confirmed this." But to conclude that every future examination will reveal the same is not supported since a different future method of examination of water, such as dipping a toe into it or mixing it with scotch, might not confirm the chemical composition. Not all examinations will reveal the chemical composition.
Good catch - that explanation does make sense.
Who cares about results
;D
Quote from: Johnny OrganDonor on January 07, 2009, 07:54:56 PM
It's invalid but not for the reason they gave. Premise b) states" that every observation or examination by microscope has confirmed this." But to conclude that every future examination will reveal the same is not supported since a different future method of examination of water, such as dipping a toe into it or mixing it with scotch, might not confirm the chemical composition. Not all examinations will reveal the chemical composition.
I think that is the answer they gave. It comes down to what we define as "observation"
"However, it is possible also that there may exist a substance that looks like water, boils as water, freezes as water, nourishes plants and life as water, and yet has a different chemical composition to what we know as water."
... or feels like water when you dip your toe, or tastes like water when you mix it with scotch.
These are different observations about a substance that behaves like water. The key was you had to infer that it was *any* possible method of observation, not "by microscope".
In a nutshell, some observations reveal that a substance behaves like water. Only one observation reveals that water is comprised of a couple of Hs and an O.
Quote from: somegirl on January 07, 2009, 07:20:47 PM
Nah, I clicked on the link and took the test before I read the rest of the thread. :P
And I am a chemist by training.
Being a chemist is not a logical choice. [laugh]
I tried that for a while.
Quote from: NAKID on January 07, 2009, 07:09:59 PM
Not a fair analogy in this case. You didn't DEFINE what the sun is composed of. They did in the first place, therefore, by calling it "water" at any time will still mean it is comprised of 2 H and 1 O atoms.
You're thinking too hard. Verily I say unto you, whosoever shall not receive this logick as a little child shall in no wise partake thereof. ;D
93%
missed the water one.
Quote from: Johnny OrganDonor on January 07, 2009, 07:54:56 PM
Question 15.
a) Water is a molecule composed of two hydrogen atoms and one oxygen atom.
b) Every observation or examination by microscope has confirmed this.
Conclusion
Therefore we can predict that every future examination of water will reveal the same chemical composition.
It's invalid but not for the reason they gave. Premise b) states" that every observation or examination by microscope has confirmed this." But to conclude that every future examination will reveal the same is not supported since a different future method of examination of water, such as dipping a toe into it or mixing it with scotch, might not confirm the chemical composition. Not all examinations will reveal the chemical composition.
But, my assertion is that the question is not saying that every future examination will have the same results. It's saying "can we
predict that every examination will reveal the same chemical composition." To which we CAN make that prediction. The explanation even says, "If one defines water as a property that contains two atoms of hydrogen and one atom of oxygen only, then the argument above is valid" and the first statement clearly does this.
It doesn't matter that there COULD be some magic new substance that has all the properties of water with a different chemical composition. That possibility has been precluded by the statement that "Water is a molecule composed of two hydrogen atoms and one oxygen atom."
Now, if the question said:
A.) The water you drink is composed of two hydrogen atoms and one oxygen atom.
B.) Examination has always proven this to be true
Conclusion: Water put on plants will always have the same composition.
I could call that invalid. As it stands, the test conclusion is incorrect. The original conclusion is valid.
I had an epiphany on the last question. The person who wrote it was thinking it terms of the etymology of the word "water" not the chemistry of the substance "water." In a sense saying that the word "water" is defined as a substance comprised of H20. In the future it is possible the word "water" may refer to a different substance.
The problem is their execution sucked. Instead of saying, "Water is a molecule composed . . ." they should have said, "Water is defined as a molecule . . ." Given the first statement as they wrote it the conclusion can be:
"Therefore we can predict that every future examination of [a molecule composed of two hydrogen atoms and one oxygen atom] will reveal the same chemical composition." And there in lies the flaw.
I stand by my call of SHENANIGANS
Quote from: superjohn on January 08, 2009, 04:56:52 AM
But, my assertion is that the question is not saying that every future examination will have the same results. It's saying "can we predict that every examination will reveal the same chemical composition." To which we CAN make that prediction.
That's a circular argument. The whole point of the question is microscopes are the way we can confirm the chemical makeup of water. That is the only way. All other ways of observing water-like behavior do not confirm the chemical makeup, but can confirm that it behaves like water. The logical gap there is what we call water may or may not be water. We have to look under a microscope to be sure.
You're saying, if we can already confirm that water is made up of H20, then we can predict that it is made up of H20. Or, because it behaves like water, it is made up of H20 - this is the logical fallacy (http://en.wikipedia.org/wiki/Begging_the_question)"begging the question"
Quote from: cloud2blue on January 08, 2009, 12:13:02 PM
The problem is their execution sucked. Instead of saying, "Water is a molecule composed . . ." they should have said, "Water is defined as a molecule . . ." Given the first statement as they wrote it the conclusion can be:
"Therefore we can predict that every future examination of [a molecule composed of two hydrogen atoms and one oxygen atom] will reveal the same chemical composition." And there in lies the flaw.
Same as above. If we already know its chemical makeup, we are not predicting anything. You're saying the wording was funky, which is valid. It is like one of those brain teasers "is there a fourth of July in England?" which is just word trickery. But, the logic in the answer is right...
If I keep reading this thread y'all are gonna give me an anurism (spelling?)
They didn't say "any future examination of a water-like substance".....
Quote from: cloud2blue on January 07, 2009, 04:30:52 PM
I call shenanigans on the last question!
+11TB on that!
I are smart. I doesn't care what tests say
Quote from: NAKID on January 07, 2009, 07:09:59 PM
Not a fair analogy in this case. You didn't DEFINE what the sun is composed of. They did in the first place, therefore, by calling it "water" at any time will still mean it is comprised of 2 H and 1 O atoms.
They gave you
one definition of water, it just happens to be the only current one.
My parallel....
An asshole is a person who does shitty things to other people.
All observations of assholes show them engaging in this behavior.
We predict that this is all further observations will confirm this to be the only definition.
However, you observe someone kick a dog and call them an asshole. Prediction disproved.
100% Yawn.