Is circular reasoning always a fallacy?
Clash Royale CLAN TAG#URR8PPP
up vote
2
down vote
favorite
Suppose the following dialogue:
...
"I accept only one notion of land property. Namely, 'I am doing my stuff here, therefore I am here".
"But this means," he responded, "you can break into any place and stay there, using this rule."
"There is another rule, though. Right to act in its most natural sense, 'I am here, therefore I am doing my stuff here."
"But do not these rules put together become circular reasoning?"
"Of course, they do," I put my head closer to him, "and this is exactly that rare case when circular reasoning is not only sufficient, but is necessary."
"But why is that? Circular reasoning never was a correct argument."
"There are many circular things happening in nature. Life forms, for example, exist only in order to produce new life forms or to prolongate their own lifetime. Is there any reason to say this can't be the case for reason itself? Why must reasoning not be circular?"
...
Can circular reasoning ever be justified? For example, we know all the words in our languages can't be defined using other words without the use of circularity. We know logic can't prove itself without circularity. Are these arguments rational? Are there any other arguments where circular reasoning is still rational?
logic fallacies
add a comment |Â
up vote
2
down vote
favorite
Suppose the following dialogue:
...
"I accept only one notion of land property. Namely, 'I am doing my stuff here, therefore I am here".
"But this means," he responded, "you can break into any place and stay there, using this rule."
"There is another rule, though. Right to act in its most natural sense, 'I am here, therefore I am doing my stuff here."
"But do not these rules put together become circular reasoning?"
"Of course, they do," I put my head closer to him, "and this is exactly that rare case when circular reasoning is not only sufficient, but is necessary."
"But why is that? Circular reasoning never was a correct argument."
"There are many circular things happening in nature. Life forms, for example, exist only in order to produce new life forms or to prolongate their own lifetime. Is there any reason to say this can't be the case for reason itself? Why must reasoning not be circular?"
...
Can circular reasoning ever be justified? For example, we know all the words in our languages can't be defined using other words without the use of circularity. We know logic can't prove itself without circularity. Are these arguments rational? Are there any other arguments where circular reasoning is still rational?
logic fallacies
add a comment |Â
up vote
2
down vote
favorite
up vote
2
down vote
favorite
Suppose the following dialogue:
...
"I accept only one notion of land property. Namely, 'I am doing my stuff here, therefore I am here".
"But this means," he responded, "you can break into any place and stay there, using this rule."
"There is another rule, though. Right to act in its most natural sense, 'I am here, therefore I am doing my stuff here."
"But do not these rules put together become circular reasoning?"
"Of course, they do," I put my head closer to him, "and this is exactly that rare case when circular reasoning is not only sufficient, but is necessary."
"But why is that? Circular reasoning never was a correct argument."
"There are many circular things happening in nature. Life forms, for example, exist only in order to produce new life forms or to prolongate their own lifetime. Is there any reason to say this can't be the case for reason itself? Why must reasoning not be circular?"
...
Can circular reasoning ever be justified? For example, we know all the words in our languages can't be defined using other words without the use of circularity. We know logic can't prove itself without circularity. Are these arguments rational? Are there any other arguments where circular reasoning is still rational?
logic fallacies
Suppose the following dialogue:
...
"I accept only one notion of land property. Namely, 'I am doing my stuff here, therefore I am here".
"But this means," he responded, "you can break into any place and stay there, using this rule."
"There is another rule, though. Right to act in its most natural sense, 'I am here, therefore I am doing my stuff here."
"But do not these rules put together become circular reasoning?"
"Of course, they do," I put my head closer to him, "and this is exactly that rare case when circular reasoning is not only sufficient, but is necessary."
"But why is that? Circular reasoning never was a correct argument."
"There are many circular things happening in nature. Life forms, for example, exist only in order to produce new life forms or to prolongate their own lifetime. Is there any reason to say this can't be the case for reason itself? Why must reasoning not be circular?"
...
Can circular reasoning ever be justified? For example, we know all the words in our languages can't be defined using other words without the use of circularity. We know logic can't prove itself without circularity. Are these arguments rational? Are there any other arguments where circular reasoning is still rational?
logic fallacies
logic fallacies
edited 4 hours ago
asked 5 hours ago
rus9384
7971216
7971216
add a comment |Â
add a comment |Â
3 Answers
3
active
oldest
votes
up vote
1
down vote
accepted
Circular reasoning - reasoning circular in form - can represent feedback loops, among other things, with perfect correctness :
WHEN asked why the economy in a certain state is in a slump, an economist replies: "A
lot of people are leaving the state. Things are very
poor in the building industry, for example, because
there is no need for new housing." Next question:
"Why are people leaving the state?" The
economist's answer: "Well, the state of the eco?
nomy is poor. People just don't seem to be able to
get jobs, with the economy being so slow at the
moment." This sequence of questions and answers
has taken us in a circle: the economy is depressed
because people are leaving, and people are leaving
because the economy is depressed. Isn't this just
the sort of argument that might be cited in a logic
text as an instance of petitio principii, the fallacy
of arguing in a circle? If so, it seems that the
economist's argument must be fallacious.
On the other hand, perhaps the circularity in his
argument could be due to the feedback loops
inherent in human behavior. If people leave, things
get worse. But if things get worse, people leave in
even greater numbers. An analogy could be to the
following case. The more overweight the diabetic
gets, the more insulin there is in his blood. The
more insulin there is in his blood, the more he
tends to eat and thereby store up more fat. Here
the process is circular, but there seems to be no
fallacy. At least, from one point of view the circle
is not vicious, since the diabetic gets fatter and
fatter. Similarly, in the previous case, the state
could become more and more economically de?
pressed, as the cycle progresses.
In mathematics, it is common practice to start
at proposition A and then prove B, then start again
at B and prove that A follows. An equivalence
proof in mathematics, of the if and only if type,
often takes this form. Although the form of proof is circular, in many instances such a proof is rightly
thought non-fallacious. And some notions that are
circular, like Russell's "set of all sets that are not
members of themselves," were found troublesome
not altogether because of the circularity involved,
but because they contain a contradiction.
These examples may suggest that circular
reasoning is not always fallacious or vicious. Some
philosophers have even carried this further to argue
that scientific reasoning itself may be inherently
circular. Hull (1967) examines the questioning of
their own methodology by evolutionary tax ono
mists. The taxa, or categories of organisms used
by biologists are applied to the study of particular
organisms to represent evolutionary descent. But
as more is learned about the principles of descent
with modification by such studies, the taxa are
refined and improved. This process has seemed
circular to some scientists, and it has been called
"groping" and "reciprocal illumination" to indicate
the suspicion of circularity. According to Hull
(1967) the process is circular only to the extent
that scientific verification of hypotheses is always
circular.
Perhaps what Hull is suggesting is something
like the following sort of process. First, a hypo?
thesis is formulated on the basis of some initial
evidence. As new evidence comes in, the hypo?
thesis is clarified and refined. However, once stated
more clearly and precisely, the hypothesis points
to new evidence that has thereby become "relevant"
or "significant." This new evidence improves the hypothesis
once again. (Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274 : 263.)
___________________________________________________________________________
References
Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274.
David L. Hull, "Certainty and Circularity in Evolutionary Biology," Evolution, logy," Evolution, vol. 21 (1967), 174-89.
add a comment |Â
up vote
1
down vote
Circular reasoning is an informal logical fallacy. Wikipedia describes it as follows:
Circular reasoning...is a logical fallacy in which the reasoner begins with what they are trying to end with. The components of a circular argument are often logically valid because if the premises are true, the conclusion must be true. Circular reasoning is not a formal logical fallacy but a pragmatic defect in an argument whereby the premises are just as much in need of proof or evidence as the conclusion, and as a consequence the argument fails to persuade.
To see this is not a formal logical fallacy note that a circular argument is valid by considering the following proof with the reiteration (R) inference rule:
If whatever English sentence P is symbolized to represent can be determined to be true, then the argument is also sound.
Nonetheless, the argument is an informal logical fallacy and it should not persuade those hearing it.
As a side note this may be an example for my question whether there exists a sound and valid argument that is informally fallacious: Can an argument be formally valid with sound premises and still be informally fallacious?
Reference
Kevin Klement's JavaScript/PHP Fitch-style natural deduction proof editor and checker http://proofs.openlogicproject.org/
add a comment |Â
up vote
0
down vote
Geoffrey refers to feedback loops as a valid example of circular reasoning. This is not correct: they can be valid but they are not circular. Instead they are an example of reasoning by induction.
It is not a implies b and b implies a. Instead it is a_n implies b_n and b_n implies a_(n+1). That is valid so long as you can start it off with a_0. For example, it is fine to say that people will distrust the economy if inflation takes off, and inflation will take off absent trust in the economy. However, you need some other reason for inflation or distrust to get going in the first place.
It is not justified to accept any proposition if the only reason for accepting it cannot be justified without assuming the original proposition.
add a comment |Â
3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
1
down vote
accepted
Circular reasoning - reasoning circular in form - can represent feedback loops, among other things, with perfect correctness :
WHEN asked why the economy in a certain state is in a slump, an economist replies: "A
lot of people are leaving the state. Things are very
poor in the building industry, for example, because
there is no need for new housing." Next question:
"Why are people leaving the state?" The
economist's answer: "Well, the state of the eco?
nomy is poor. People just don't seem to be able to
get jobs, with the economy being so slow at the
moment." This sequence of questions and answers
has taken us in a circle: the economy is depressed
because people are leaving, and people are leaving
because the economy is depressed. Isn't this just
the sort of argument that might be cited in a logic
text as an instance of petitio principii, the fallacy
of arguing in a circle? If so, it seems that the
economist's argument must be fallacious.
On the other hand, perhaps the circularity in his
argument could be due to the feedback loops
inherent in human behavior. If people leave, things
get worse. But if things get worse, people leave in
even greater numbers. An analogy could be to the
following case. The more overweight the diabetic
gets, the more insulin there is in his blood. The
more insulin there is in his blood, the more he
tends to eat and thereby store up more fat. Here
the process is circular, but there seems to be no
fallacy. At least, from one point of view the circle
is not vicious, since the diabetic gets fatter and
fatter. Similarly, in the previous case, the state
could become more and more economically de?
pressed, as the cycle progresses.
In mathematics, it is common practice to start
at proposition A and then prove B, then start again
at B and prove that A follows. An equivalence
proof in mathematics, of the if and only if type,
often takes this form. Although the form of proof is circular, in many instances such a proof is rightly
thought non-fallacious. And some notions that are
circular, like Russell's "set of all sets that are not
members of themselves," were found troublesome
not altogether because of the circularity involved,
but because they contain a contradiction.
These examples may suggest that circular
reasoning is not always fallacious or vicious. Some
philosophers have even carried this further to argue
that scientific reasoning itself may be inherently
circular. Hull (1967) examines the questioning of
their own methodology by evolutionary tax ono
mists. The taxa, or categories of organisms used
by biologists are applied to the study of particular
organisms to represent evolutionary descent. But
as more is learned about the principles of descent
with modification by such studies, the taxa are
refined and improved. This process has seemed
circular to some scientists, and it has been called
"groping" and "reciprocal illumination" to indicate
the suspicion of circularity. According to Hull
(1967) the process is circular only to the extent
that scientific verification of hypotheses is always
circular.
Perhaps what Hull is suggesting is something
like the following sort of process. First, a hypo?
thesis is formulated on the basis of some initial
evidence. As new evidence comes in, the hypo?
thesis is clarified and refined. However, once stated
more clearly and precisely, the hypothesis points
to new evidence that has thereby become "relevant"
or "significant." This new evidence improves the hypothesis
once again. (Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274 : 263.)
___________________________________________________________________________
References
Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274.
David L. Hull, "Certainty and Circularity in Evolutionary Biology," Evolution, logy," Evolution, vol. 21 (1967), 174-89.
add a comment |Â
up vote
1
down vote
accepted
Circular reasoning - reasoning circular in form - can represent feedback loops, among other things, with perfect correctness :
WHEN asked why the economy in a certain state is in a slump, an economist replies: "A
lot of people are leaving the state. Things are very
poor in the building industry, for example, because
there is no need for new housing." Next question:
"Why are people leaving the state?" The
economist's answer: "Well, the state of the eco?
nomy is poor. People just don't seem to be able to
get jobs, with the economy being so slow at the
moment." This sequence of questions and answers
has taken us in a circle: the economy is depressed
because people are leaving, and people are leaving
because the economy is depressed. Isn't this just
the sort of argument that might be cited in a logic
text as an instance of petitio principii, the fallacy
of arguing in a circle? If so, it seems that the
economist's argument must be fallacious.
On the other hand, perhaps the circularity in his
argument could be due to the feedback loops
inherent in human behavior. If people leave, things
get worse. But if things get worse, people leave in
even greater numbers. An analogy could be to the
following case. The more overweight the diabetic
gets, the more insulin there is in his blood. The
more insulin there is in his blood, the more he
tends to eat and thereby store up more fat. Here
the process is circular, but there seems to be no
fallacy. At least, from one point of view the circle
is not vicious, since the diabetic gets fatter and
fatter. Similarly, in the previous case, the state
could become more and more economically de?
pressed, as the cycle progresses.
In mathematics, it is common practice to start
at proposition A and then prove B, then start again
at B and prove that A follows. An equivalence
proof in mathematics, of the if and only if type,
often takes this form. Although the form of proof is circular, in many instances such a proof is rightly
thought non-fallacious. And some notions that are
circular, like Russell's "set of all sets that are not
members of themselves," were found troublesome
not altogether because of the circularity involved,
but because they contain a contradiction.
These examples may suggest that circular
reasoning is not always fallacious or vicious. Some
philosophers have even carried this further to argue
that scientific reasoning itself may be inherently
circular. Hull (1967) examines the questioning of
their own methodology by evolutionary tax ono
mists. The taxa, or categories of organisms used
by biologists are applied to the study of particular
organisms to represent evolutionary descent. But
as more is learned about the principles of descent
with modification by such studies, the taxa are
refined and improved. This process has seemed
circular to some scientists, and it has been called
"groping" and "reciprocal illumination" to indicate
the suspicion of circularity. According to Hull
(1967) the process is circular only to the extent
that scientific verification of hypotheses is always
circular.
Perhaps what Hull is suggesting is something
like the following sort of process. First, a hypo?
thesis is formulated on the basis of some initial
evidence. As new evidence comes in, the hypo?
thesis is clarified and refined. However, once stated
more clearly and precisely, the hypothesis points
to new evidence that has thereby become "relevant"
or "significant." This new evidence improves the hypothesis
once again. (Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274 : 263.)
___________________________________________________________________________
References
Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274.
David L. Hull, "Certainty and Circularity in Evolutionary Biology," Evolution, logy," Evolution, vol. 21 (1967), 174-89.
add a comment |Â
up vote
1
down vote
accepted
up vote
1
down vote
accepted
Circular reasoning - reasoning circular in form - can represent feedback loops, among other things, with perfect correctness :
WHEN asked why the economy in a certain state is in a slump, an economist replies: "A
lot of people are leaving the state. Things are very
poor in the building industry, for example, because
there is no need for new housing." Next question:
"Why are people leaving the state?" The
economist's answer: "Well, the state of the eco?
nomy is poor. People just don't seem to be able to
get jobs, with the economy being so slow at the
moment." This sequence of questions and answers
has taken us in a circle: the economy is depressed
because people are leaving, and people are leaving
because the economy is depressed. Isn't this just
the sort of argument that might be cited in a logic
text as an instance of petitio principii, the fallacy
of arguing in a circle? If so, it seems that the
economist's argument must be fallacious.
On the other hand, perhaps the circularity in his
argument could be due to the feedback loops
inherent in human behavior. If people leave, things
get worse. But if things get worse, people leave in
even greater numbers. An analogy could be to the
following case. The more overweight the diabetic
gets, the more insulin there is in his blood. The
more insulin there is in his blood, the more he
tends to eat and thereby store up more fat. Here
the process is circular, but there seems to be no
fallacy. At least, from one point of view the circle
is not vicious, since the diabetic gets fatter and
fatter. Similarly, in the previous case, the state
could become more and more economically de?
pressed, as the cycle progresses.
In mathematics, it is common practice to start
at proposition A and then prove B, then start again
at B and prove that A follows. An equivalence
proof in mathematics, of the if and only if type,
often takes this form. Although the form of proof is circular, in many instances such a proof is rightly
thought non-fallacious. And some notions that are
circular, like Russell's "set of all sets that are not
members of themselves," were found troublesome
not altogether because of the circularity involved,
but because they contain a contradiction.
These examples may suggest that circular
reasoning is not always fallacious or vicious. Some
philosophers have even carried this further to argue
that scientific reasoning itself may be inherently
circular. Hull (1967) examines the questioning of
their own methodology by evolutionary tax ono
mists. The taxa, or categories of organisms used
by biologists are applied to the study of particular
organisms to represent evolutionary descent. But
as more is learned about the principles of descent
with modification by such studies, the taxa are
refined and improved. This process has seemed
circular to some scientists, and it has been called
"groping" and "reciprocal illumination" to indicate
the suspicion of circularity. According to Hull
(1967) the process is circular only to the extent
that scientific verification of hypotheses is always
circular.
Perhaps what Hull is suggesting is something
like the following sort of process. First, a hypo?
thesis is formulated on the basis of some initial
evidence. As new evidence comes in, the hypo?
thesis is clarified and refined. However, once stated
more clearly and precisely, the hypothesis points
to new evidence that has thereby become "relevant"
or "significant." This new evidence improves the hypothesis
once again. (Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274 : 263.)
___________________________________________________________________________
References
Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274.
David L. Hull, "Certainty and Circularity in Evolutionary Biology," Evolution, logy," Evolution, vol. 21 (1967), 174-89.
Circular reasoning - reasoning circular in form - can represent feedback loops, among other things, with perfect correctness :
WHEN asked why the economy in a certain state is in a slump, an economist replies: "A
lot of people are leaving the state. Things are very
poor in the building industry, for example, because
there is no need for new housing." Next question:
"Why are people leaving the state?" The
economist's answer: "Well, the state of the eco?
nomy is poor. People just don't seem to be able to
get jobs, with the economy being so slow at the
moment." This sequence of questions and answers
has taken us in a circle: the economy is depressed
because people are leaving, and people are leaving
because the economy is depressed. Isn't this just
the sort of argument that might be cited in a logic
text as an instance of petitio principii, the fallacy
of arguing in a circle? If so, it seems that the
economist's argument must be fallacious.
On the other hand, perhaps the circularity in his
argument could be due to the feedback loops
inherent in human behavior. If people leave, things
get worse. But if things get worse, people leave in
even greater numbers. An analogy could be to the
following case. The more overweight the diabetic
gets, the more insulin there is in his blood. The
more insulin there is in his blood, the more he
tends to eat and thereby store up more fat. Here
the process is circular, but there seems to be no
fallacy. At least, from one point of view the circle
is not vicious, since the diabetic gets fatter and
fatter. Similarly, in the previous case, the state
could become more and more economically de?
pressed, as the cycle progresses.
In mathematics, it is common practice to start
at proposition A and then prove B, then start again
at B and prove that A follows. An equivalence
proof in mathematics, of the if and only if type,
often takes this form. Although the form of proof is circular, in many instances such a proof is rightly
thought non-fallacious. And some notions that are
circular, like Russell's "set of all sets that are not
members of themselves," were found troublesome
not altogether because of the circularity involved,
but because they contain a contradiction.
These examples may suggest that circular
reasoning is not always fallacious or vicious. Some
philosophers have even carried this further to argue
that scientific reasoning itself may be inherently
circular. Hull (1967) examines the questioning of
their own methodology by evolutionary tax ono
mists. The taxa, or categories of organisms used
by biologists are applied to the study of particular
organisms to represent evolutionary descent. But
as more is learned about the principles of descent
with modification by such studies, the taxa are
refined and improved. This process has seemed
circular to some scientists, and it has been called
"groping" and "reciprocal illumination" to indicate
the suspicion of circularity. According to Hull
(1967) the process is circular only to the extent
that scientific verification of hypotheses is always
circular.
Perhaps what Hull is suggesting is something
like the following sort of process. First, a hypo?
thesis is formulated on the basis of some initial
evidence. As new evidence comes in, the hypo?
thesis is clarified and refined. However, once stated
more clearly and precisely, the hypothesis points
to new evidence that has thereby become "relevant"
or "significant." This new evidence improves the hypothesis
once again. (Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274 : 263.)
___________________________________________________________________________
References
Douglas N. Walton, 'Are Circular Arguments Necessarily Vicious?', American Philosophical Quarterly, Vol. 22, No. 4 (Oct., 1985), pp. 263-274.
David L. Hull, "Certainty and Circularity in Evolutionary Biology," Evolution, logy," Evolution, vol. 21 (1967), 174-89.
answered 3 hours ago
Geoffrey Thomas
17.9k21470
17.9k21470
add a comment |Â
add a comment |Â
up vote
1
down vote
Circular reasoning is an informal logical fallacy. Wikipedia describes it as follows:
Circular reasoning...is a logical fallacy in which the reasoner begins with what they are trying to end with. The components of a circular argument are often logically valid because if the premises are true, the conclusion must be true. Circular reasoning is not a formal logical fallacy but a pragmatic defect in an argument whereby the premises are just as much in need of proof or evidence as the conclusion, and as a consequence the argument fails to persuade.
To see this is not a formal logical fallacy note that a circular argument is valid by considering the following proof with the reiteration (R) inference rule:
If whatever English sentence P is symbolized to represent can be determined to be true, then the argument is also sound.
Nonetheless, the argument is an informal logical fallacy and it should not persuade those hearing it.
As a side note this may be an example for my question whether there exists a sound and valid argument that is informally fallacious: Can an argument be formally valid with sound premises and still be informally fallacious?
Reference
Kevin Klement's JavaScript/PHP Fitch-style natural deduction proof editor and checker http://proofs.openlogicproject.org/
add a comment |Â
up vote
1
down vote
Circular reasoning is an informal logical fallacy. Wikipedia describes it as follows:
Circular reasoning...is a logical fallacy in which the reasoner begins with what they are trying to end with. The components of a circular argument are often logically valid because if the premises are true, the conclusion must be true. Circular reasoning is not a formal logical fallacy but a pragmatic defect in an argument whereby the premises are just as much in need of proof or evidence as the conclusion, and as a consequence the argument fails to persuade.
To see this is not a formal logical fallacy note that a circular argument is valid by considering the following proof with the reiteration (R) inference rule:
If whatever English sentence P is symbolized to represent can be determined to be true, then the argument is also sound.
Nonetheless, the argument is an informal logical fallacy and it should not persuade those hearing it.
As a side note this may be an example for my question whether there exists a sound and valid argument that is informally fallacious: Can an argument be formally valid with sound premises and still be informally fallacious?
Reference
Kevin Klement's JavaScript/PHP Fitch-style natural deduction proof editor and checker http://proofs.openlogicproject.org/
add a comment |Â
up vote
1
down vote
up vote
1
down vote
Circular reasoning is an informal logical fallacy. Wikipedia describes it as follows:
Circular reasoning...is a logical fallacy in which the reasoner begins with what they are trying to end with. The components of a circular argument are often logically valid because if the premises are true, the conclusion must be true. Circular reasoning is not a formal logical fallacy but a pragmatic defect in an argument whereby the premises are just as much in need of proof or evidence as the conclusion, and as a consequence the argument fails to persuade.
To see this is not a formal logical fallacy note that a circular argument is valid by considering the following proof with the reiteration (R) inference rule:
If whatever English sentence P is symbolized to represent can be determined to be true, then the argument is also sound.
Nonetheless, the argument is an informal logical fallacy and it should not persuade those hearing it.
As a side note this may be an example for my question whether there exists a sound and valid argument that is informally fallacious: Can an argument be formally valid with sound premises and still be informally fallacious?
Reference
Kevin Klement's JavaScript/PHP Fitch-style natural deduction proof editor and checker http://proofs.openlogicproject.org/
Circular reasoning is an informal logical fallacy. Wikipedia describes it as follows:
Circular reasoning...is a logical fallacy in which the reasoner begins with what they are trying to end with. The components of a circular argument are often logically valid because if the premises are true, the conclusion must be true. Circular reasoning is not a formal logical fallacy but a pragmatic defect in an argument whereby the premises are just as much in need of proof or evidence as the conclusion, and as a consequence the argument fails to persuade.
To see this is not a formal logical fallacy note that a circular argument is valid by considering the following proof with the reiteration (R) inference rule:
If whatever English sentence P is symbolized to represent can be determined to be true, then the argument is also sound.
Nonetheless, the argument is an informal logical fallacy and it should not persuade those hearing it.
As a side note this may be an example for my question whether there exists a sound and valid argument that is informally fallacious: Can an argument be formally valid with sound premises and still be informally fallacious?
Reference
Kevin Klement's JavaScript/PHP Fitch-style natural deduction proof editor and checker http://proofs.openlogicproject.org/
edited 4 hours ago
answered 4 hours ago
Frank Hubeny
3,4732834
3,4732834
add a comment |Â
add a comment |Â
up vote
0
down vote
Geoffrey refers to feedback loops as a valid example of circular reasoning. This is not correct: they can be valid but they are not circular. Instead they are an example of reasoning by induction.
It is not a implies b and b implies a. Instead it is a_n implies b_n and b_n implies a_(n+1). That is valid so long as you can start it off with a_0. For example, it is fine to say that people will distrust the economy if inflation takes off, and inflation will take off absent trust in the economy. However, you need some other reason for inflation or distrust to get going in the first place.
It is not justified to accept any proposition if the only reason for accepting it cannot be justified without assuming the original proposition.
add a comment |Â
up vote
0
down vote
Geoffrey refers to feedback loops as a valid example of circular reasoning. This is not correct: they can be valid but they are not circular. Instead they are an example of reasoning by induction.
It is not a implies b and b implies a. Instead it is a_n implies b_n and b_n implies a_(n+1). That is valid so long as you can start it off with a_0. For example, it is fine to say that people will distrust the economy if inflation takes off, and inflation will take off absent trust in the economy. However, you need some other reason for inflation or distrust to get going in the first place.
It is not justified to accept any proposition if the only reason for accepting it cannot be justified without assuming the original proposition.
add a comment |Â
up vote
0
down vote
up vote
0
down vote
Geoffrey refers to feedback loops as a valid example of circular reasoning. This is not correct: they can be valid but they are not circular. Instead they are an example of reasoning by induction.
It is not a implies b and b implies a. Instead it is a_n implies b_n and b_n implies a_(n+1). That is valid so long as you can start it off with a_0. For example, it is fine to say that people will distrust the economy if inflation takes off, and inflation will take off absent trust in the economy. However, you need some other reason for inflation or distrust to get going in the first place.
It is not justified to accept any proposition if the only reason for accepting it cannot be justified without assuming the original proposition.
Geoffrey refers to feedback loops as a valid example of circular reasoning. This is not correct: they can be valid but they are not circular. Instead they are an example of reasoning by induction.
It is not a implies b and b implies a. Instead it is a_n implies b_n and b_n implies a_(n+1). That is valid so long as you can start it off with a_0. For example, it is fine to say that people will distrust the economy if inflation takes off, and inflation will take off absent trust in the economy. However, you need some other reason for inflation or distrust to get going in the first place.
It is not justified to accept any proposition if the only reason for accepting it cannot be justified without assuming the original proposition.
answered 5 mins ago
Josiah
1212
1212
add a comment |Â
add a comment |Â
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fphilosophy.stackexchange.com%2fquestions%2f55574%2fis-circular-reasoning-always-a-fallacy%23new-answer', 'question_page');
);
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password