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1 All griznoxes chorble happily. Premise
2 A floober is a type of griznox. Premise
3 Therefore, floobers chorble happily. Syllogism, lines 1,2

You don't need to be a world-class floober expert to evaluate this argument, either.

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Lewis Carroll, a logician, has developed many whimsical examples of syllogisms and simple reasoning. (Relatedly,note how the social context of Carroll's examples demonstrates some feminist issues inteaching logic .)

As you've noticed, the form of the argument is the same in all these.If you are assured that the first two premises are true, then, without any true understanding,you (or a computer) can automatically come up with the conclusion. A syllogism is one example of a inference rule that is, a rule form that a computer can use to deduce new facts from known ones.

Some non-proofs

Of course, not all arguments are valid proofs. Identifying invalid proofs is just as interesting as identifying valid ones.

Homer: Ah, not a bear in sight. The Bear Patrol must be working. Lisa: That's specious reasoning, Dad. Homer: Thank you, honey.Lisa: By your logic, this rock keeps tigers away. Homer: Oh? How does it work?Lisa: It doesn't work. Homer: Uh-huh.Lisa: It's just a stupid rock. Homer: Uh-huh.Lisa: But I don't see any tigers around here, do you? [pause]Homer: Lisa, I want to buy your rock! [A moment's hesitationand money changes hands.] (From The Simpsons Much Apu About Nothing .)

If Lisa isn't around, who will identify specious reasoning for us? We can certainly use her approach of finding other particular examplesthat follow the same argument, yet lead to a clearly erroneous conclusion.

Suppose that my friend makes the following argument:

1 Warm cola tastes bad. Premise
2 Warm salt-water tastes bad. Premise
3 Therefore, mixing them together tastes bad. Common-sense conclusion, lines 1,2
I'm skeptical, so I have a sip; sure enough, the conclusion is indeed true. But is the proof correctdoes thecommon-sense conclusionrule actually hold? In order to refute the form of the argument, we can trysimilar arguments which have the same form but a false conclusion (as Lisa did).
1 Ice-cold coke tastes good. Premise
2 Ice coffee tastes good. Premise
3 Therefore, mixing them together tastes good. Common-sense conclusion, lines 1 and 2.
After another unfortunate sip, I verify that this conclusion is not true, and therefore my friend's reasoning is at fault.

My friend responds by claiming that thecommon-sense conclusionis too valid; the rule is that bad-taste is preserved upon mixing,not that any taste is preserved. While I'm inclined to believe that, we realize we can stilltest this more refined rule: can you come up with an instance of mixing together bad-tasting thingsand ever getting a yummy result? (Say, salt and flour, which can be mixed and baked to get delicious saltines!The argument continues, about whether the form of the argument precludes baking, and so on.)

The end result (after I take some antacid) is that we have a clearer understanding ofthe initially vaguecommon-sense conclusion, and stricter rules about when it applies.Thus, refining the argument has led us to a greater understanding.

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Questions & Answers

What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
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Source:  OpenStax, Intro to logic. OpenStax CNX. Jan 29, 2008 Download for free at http://cnx.org/content/col10154/1.20
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