truth and validity
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TRUTH AND VALADITY
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VALID ARGUMENT
Valid argument is an argument such that it
is impossile !or premises to e true and
the conclusion !alse means in "hich the
conclusion !ollo"s "hich strict necessit#!rom the conclusion e$g$
All tele%ision net"or&s are media companies$
N'( is a tele%ision net"or&$
There!ore N'( is a media compan#$
Valid argument is an argument such that it
is impossile !or premises to e true and
the conclusion !alse means in "hich the
conclusion !ollo"s "hich strict necessit#!rom the conclusion e$g$
All tele%ision net"or&s are media companies$
N'( is a tele%ision net"or&$
There!ore N'( is a media compan#$
Valid argument is an argument such that it
is impossile !or premises to e true and
the conclusion !alse means in "hich the
conclusion !ollo"s "hich strict necessit#!rom the conclusion e$g$
All tele%ision net"or&s are media companies$
N'( is a tele%ision net"or&$
There!ore N'( is a media compan#$
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INVALID ARGUMENT
An in%alid argument is an argument such that itis possile !or premises to e true and
conclusion !alse$ In in%alid arguments the
conclusion does not !ollo" "ith strict necessit#
!rom premises) e%en though it claimed to e$g$
All an&s are !inancial institutions$
*ells +argo is a !inancial institution$There!ore
N'( is a media compan#$
There!ore) *ells +argo is a an&$
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,-UND ARGUMENT
A sound argument is a deductive
argument that is valid and has all true
premises. Both condition must be metfor an argument to be sound. A sound
argument, therefore, is what is meant
by a good deductive argument in the
fullest sense of the term.
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UN,-UND ARGUMENT
An unsound argument is a deductive
argument that is invalid has one or more
false premises, or both. For anargument to be unsound, the false
premise or premises must actually be
needed to support the conclusion.
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INDU(TIVE ARGUMENT
Inductive argument is the one in which
the premises are claimed to support the
conclusion in such a way that it isimprobable that the premises be true and
the conclusion false.
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,TR-NG ARGUMENT
It is an inductive argument such that it is
improbable that the premises be true and
the conclusion false. In such arguments,
the conclusion follows probably from the
premises e.g.
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All dinosaur bones discovered to this day
have been at least 5 million years old.
!herefore, probably the ne"t dinosaur
bone to be found will be at least 5 million
years old. In this argument the premise is
actually true, the conclusion is probablytrue. #o the argument is strong.
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*EA. ARGUMENT
It is an inductive argument such that the
conclusion does not follow probably from
the premises, even through it claimed to.
e.g.
$uring the past fifty years, inflation has
consistently reduced the value of %a&istanirupee. !herefore, industrial productivity
will probably increase in the years ahead.
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In this argument, the premises is actuallytrue and the conclusion is probably true in
the actual world, but the probability of theconclusion is no way based on theassumption that the premises is true.
Because there is no direct connectionbetween inflation and increased industrialproductivity, the premise is irrelevant to theconclusion and it provide no probabilistic
support for it. !he conclusion is probablytrue independently of the premise. As aresult the conclusion is wea&.
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(-GENT ARGUMENT
It is an inductive argument that is strong and has all truepremises. In other words a cogent argument is theinductive analogue of a sound deductive argument andis what is meant by a good inductive argument without'ualification. Because the conclusion of a cogent
argument is genuinely supported by true premises, itfollows that the conclusion of every cogent argument isprobably true. !here is a difference between sound andcogent argument. In a sound argument it is onlynecessary that the premises be true and nothing more.(hile in a cogent argument the premises must not onlybe true, they must also not ignore some important pieceof evidence that outweighs the given evidence andentail a 'uite different conclusion. e.g.
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#wimming in #ardaryab is usually lots of
fun. !oday the water is warm, the surf is
gentle and on this beech there are no
dangerous currents. !herefore, it would be
fun to go swimming here now.
If the premises reflect all the important
factors then the argument is cogent. But if
they ignore the fact then the argument is
not cogent. !hus, for cogency thepremises must not only be true but also
not over loo& some important factors.
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UN(-GENT ARGUMENT
An uncogent argument is an inductive
argument that is wea& has one or more
false premises or both.
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$IA)*A+ #-(I) /A*I-0#
A1!2*A!I/2# -%2 !-#!A!2+2!# A$ A*)0+2!
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INDEDU(TIVEARGUMENT
,TR-NG *EA.
(-GENT UN(-GENT
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,TATEMENT
True
+alse
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DEDU(TIVEARGUMENT
VALID INVALID
,-UND UN,-UND
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+ALLA(IE,
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+ALLA(Y
A fallacy is an argument which appears to be
valid but in reality it is not so. It is an invalid
argument which is camouflaged and which can
deceive or mislead us by a show of truth. It is,so to spea&, a trap, something !ric&y or hidden.
Being mista&es in reasoning, fallacies arisesfrom the violation of one or other of the
principles on which the correctness of
reasoning depends.
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A fallacy may be committed unintentionally or intentionally.
(hen the fallacy is committed unintentionally it is called
paralogism.
A$
when it is committed intentionally then it is called sophism.
Fallacies can be formal and informal.
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+-RMAL +ALLA(Y
A formal fallacy is one that can be
detected by analy3ing the form of an
argument, such fallacies affect only
deductive argument.
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IN+-RMAL +ALLA(Y
An informal fallacy is one that can be
identified only by analy3ing the content of
an argument, such fallacies can affect
both deductive and inductive arguments.
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+ALLA(IE, -+ RELEVAN(E
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THE +ALLA(Y -+ RELEVAN(E
!he fallacy of relevance share the common
characteristics that the argument in which they
occur have premises that are logically irrelevant
to the conclusion. 4et the premises are relevant
psychologically, so the conclusion may seem to
follow from the premises, even though it does not
follow logically.
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In an argument that commit fallacy of
relevance, the connection between
premises and conclusion is emotional. !o
identify a fallacy of relevance, one must be
able to distinguish genuine evidence from
various forms of emotional appeal.
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