View source for Logical fallacy

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A '''logical fallacy''' is an error in logical argumentation. It is a flaw in the structure of an argument, which is said to invalidate the argument, as opposed to representing an error in its premises. A fallacy within an argument is independent of the [[truth]], and does not necessarily imply anything about the argument's premises or its conclusion. It is simply an error which violates the rules of [[logic]]. Nevertheless, arguments that are derived from a logical fallacy often lead to an incorrect conclusion due to faulty reasoning.
  
== Evolutionism logic ==
Many everyday [[evolutionists]], including those without advanced degrees in [[science]], have been known to layer fallacy upon fallacy to support their claims. [[logical fallacy (EvoWiki)|EvoWiki's page on fallacies]], for example, is itself a case-study in fallacies made by evolutionists. Of course, many everyday creationists commit logical fallacies as well.  This is to be expected when one polls the opinions of hobbyists with limited or no scientific training.

But fallacy is not limited to everyday evolutionists.  In fact, books written by well-known evolutionists such as [[Stephen Jay Gould]] and [[Ernst Mayr]] commit logical fallacies so transparent that one is left wondering why these evolutionists, who one would think are trained to think clearly, make so many basic errors in logic.

One of the answers to this question may lie in evolutionary biology curricula.

In order to earn a degree in evolutionary biology from USC[http://web.archive.org/20060210061505/www.biology.ucsc.edu/eeb/grad/phddegree.html], an individual must take the following classes:

* BIOL 250A Advanced Organismal Biology
* BIOL 250B Scientific Skills
* BIOL 279 Evolutionary Ecology
* BIOL 281 Lab Discussion Meetings 
* BIOL 293 Readings in Ecology and Evolutionary Biology
* BIOL 294 EEB Seminar Series 
* BIOL 297 Independent Study 
* BIOL 299 Dissertation Research

This curriculum is completely lacking in any courses in [[philosophy of science]], [[logic]], critical thinking, or any other coursework which teaches the students the basis of logic and logical fallacies.

The course that comes closest, Scientific Skills, is described as follows:
{{cquote|Exposes graduate students to teaching skills, understanding the scientific method, searching and organizing literature, grant proposal writing, data management and presentation, and scientific speaking. Students are evaluated on their participation and the quality of a written research proposal.}}

The students appear to learn a great deal about grant-writing, but absolutely nothing about philosophy of science. The vast majority of evolutionary biology programs are similar to this one.  Harvard's program is even less structured than this one, and like this one, requires no coursework in philosophy of science, logic, or critical thinking.  Aspiring PhDs are not taught ''anything'' of the nuances of [[philosophy of science]], logic, logical fallacies, critical thinking, or metaphysics.  They graduate with a PhD while still totally ignorant on the topics that are so key to the creation-evolution controversy.

What they are taught is a great number of facts about [[evolution]], and in order to pass their exams, they must be able to repeat all the facts about evolution they have been taught.  They need not think critically.  They need not evaluate analytically.  They need only repeat what they have been told. What critical thinking does occur (in their dissertation research, for instance) is always done within the materialistic and evolutionistic paradigm.  They may think critically, but not too critically. And when they graduate and face creationists on the field of philosophy of science, they are steeped in the ideas of evolution, convinced it is the truth and science, and become infuriated by creationists who have not earned a PhD who somehow feel entitled to question their dogmas.

Many philosophers of science, even evolutionists, recognize this problem, and frequently point out the foolish arguments made by even the most prominent evolutionists.  For examples, see the article - [[Falsifiability]].

==Fallacies==
<table style="border:1px solid #AAAAAA; background: #EDF1F1; float:right; width:100px; margin-left:15px;">
<tr><td>{{fallacy|type}}
<tr><td>Use the <nowiki>{{fallacy|type}}</nowiki> template to insert the above warning on a page containing a ''logical fallacy''. Replace the word "type" with the name of the fallacy to link the warning label to the appropriate page.
</table>

===Ad hominem===
: ''Main Article: [[Ad hominem]]''

An ad hominem ([[Latin]]: "To the Man") is an argument which attacks people holding a contrary view, rather than attacking specific points regarding their view.

For example:
* C: "I'm a creationist because I find [[flood geology]], [[irreducible complexity]], and [[specified complexity]] to be convincing arguments;"
* E: "But you're not a scientist; your opinions are not valid."

The evolutionist in this case has dismissed opinions on the basis of credentials, without ever addressing the merits of the actual argument.

===Argument from result===
An argument from result attempts to argue against an idea based on what would happen if that theory were true.

For example:
* E: "If creationism were true then homosexuality would be wrong; therefore, creationism isn't true."

===Overgeneralization===
: ''Main Article: [[Overgeneralization]]''

An overgeneralization is an argument which makes a statement so broad as to be classified as an exceeding the original point that was trying to be proved.

For example:
* E: "Creationists aim to not only destroy science in an effort to bolster their claims, they mean to redefine the United States of America, eviscerate the Constitution, and effectively dismantle American democracy, by instituting religious indoctrination in the schools and halls of public policy making."  

He has generalized about the "secret goals of all creationists" to such a degree that apparently even little 11 year-olds reading the story of [[Noah]] and believing it are involved in this conspiracy to destroy the world.

===Non sequitur===
: ''Main Article: [[Non sequitur]]''

Non sequitur (Latin: "It does not follow") is an argument which moves from a premise to a conclusion where no connection exists between the two.

For example:
* E: "As evidence for common descent: The structures that all known organisms use to perform these four basic processes are all quite similar, in spite of the odds. All known living things use polymers to perform these four basic functions. Organic chemists have synthesized hundreds of different polymers, yet the only ones used by life, irrespective of species, are polynucleotides, polypeptides, and [[polysaccharides]]."  

The argument is in its essential form is, "Because different forms of life are structured in similar ways, they are more likely to be related." The mere fact that things are similar does not require them to be related. God, the intelligent Creator may use similar chemical mechanisms to construct life, but that is not evidence that the forms of life are genetically related. The chemical similarity of all life is consistent with both creation and evolution and thus using it to defend [[common descent]] is a [[non sequitur]].

===Proof by authority===
An argument which is based on a person's authority, rather than on the merits of the authority's position.

* E: "The scientific consensus today is that evolution is science and creation is not.  Therefore evolution is the scientific position."

He has argued simply that because "most scientists think this way," it must be true.  He has failed, however, to address the merits.  Science does not care about authority.  It cares about the merits of a position, the factual data, not presuppositions or bias.  The "majority opinion" can be the result of any number of things, including the power of people in power to promote those who agree with their ideological biases, and discriminate against those who do not.  But those things have nothing to do with the merit of the argument.

===Proof by assertion===
An argument which simply states something as true without evidence or argument to support it.

* E: "While some creationists refer to themselves as "scientific creationists" or "creation scientists", very little of creationism is actually scientific - and that is either falsified, poorly evidenced or in agreement with mainstream science." [http://wiki.cotch.net/index.php/Creationism]

The article does not provide any hard evidence to support its conclusion about the "unscientific nature" of creationism.  It says that "science" is one thing and not another, and then says that creationism violates that definition.  It does not defend its definition, and it does not explain how creationism violates that definition.  The article has said, "Creationism is false!" and the reader is meant to believe without real data to support it.

===Circular reasoning===
: ''Main Article: [[Circular reasoning]]''

Circular reasoning is any attempt to prove something by first asserting it and then trying to "prove" it through any number of intervening conditional statements.

* E: "The earth cannot be merely six thousand years old (or ten thousand), because we have found life-forms that [[carbon-14 dating]] shows to be forty thousand years old."

How do you know that? Your very model for dating depends on a certain [[isotope]] of [[carbon]] being in dynamic equilibrium in the atmosphere for a long time. Now if the earth were really as old as you say, that might be the case. But if it isn't, then your baseline, and thus your derived age for the sample, are too high.

===Proving too much===
The use of a classification which includes too many things in the classification.

* E: Creationism is not scientific because it is not observable.

The Big Bang, Space-time, and Quark theory are not observable either yet most evolutionary scientists tend to believe such.  Are they then not scientific?

===Double standard===
The unequal use of a criterion, by applying it differently in different cases.

* E: Creationism is not scientific because it is not falsifiable.

Common descent is also unfalsifiable.  It cannot be proven wrong, because we cannot directly observe the ancient past.  Is it also then unscientific?

===Your theory does not work under my theory, so your theory must be wrong===
: ''Main article: [[Your theory does not work under my theory, so your theory must be wrong]]''

A theory is judged by the premises and assumptions of another theory, rather than being judged against its own premises and assumptions.

* E: Creationism can't be right -- the fossil record shows that fossils were laid down over millions of years.

Creationists challenge your assumptions about [[radiometric dating]], the [[geologic column]], and [[fossilization]], and instead see the fossils as laid down in the [[Global flood]].  Thus your "evidence" against creationism is no evidence at all when stripped of your unfalsifiable assumptions.

===Manufacturing facts from a theory===
: ''Main article:  [[Manufacturing facts from a theory]]''

An undemonstrated, unobserved idea is stated as fact because it comports with a particular theory.

* E: Humans share a common ancestor with the apes.

Actually, this fact cannot be tested without time machines.  It is only ''assumed'' to be true because it comports with the ''theory'' of [[common descent]].  But the theory of [[common descent]] can only derive from ''facts'' indicating that all life is related.  Unobservable, untestable speculations cannot be stated as facts simply because they derive from the theory.  They can only be stated as facts if they can be observed.

===Genetic fallacy===
According to a leading logical fallacy website, "The Genetic Fallacy is the most general fallacy of irrelevancy involving the origins or history of an idea. It is fallacious to either endorse or condemn an idea based on its past—rather than on its present—merits or demerits, unless its past in some way affects its present value. For instance, the origin of evidence can be quite relevant to its evaluation, especially in historical investigations. The origin of testimony—whether first hand, hearsay, or rumor—carries weight in evaluating it. 

In contrast, the value of many scientific ideas can be objectively evaluated by established techniques, so that the origin or history of the idea is irrelevant to its value." [http://www.fallacyfiles.org/genefall.html]

===Tautology===
: ''Main Article: [[Tautology]]''

A tautology is a statement that is true under all circumstances, such that the statement carries no meaning.
ex: "all unmarried men are bachelors," "free gift," etc. People who don't believe in materialistic evolution would generally agree that "design requires a designer" is a tautology. For this reason it is very strange for people to deny this claim; the only reasonable excuse would be to demonstrate that the "design" is not "design." This is a high priority interest for many evolutionists who wish to refute the idea of a designer so that they may "suppress the truth in unrighteousness."<ref>[http://www.biblegateway.com/passage/?search=Romans+1:18-23&version=NIV Romans 1:18-23]</ref>

===Contradiction===
: ''Main Article: [[Contradiction]]''

A contradiction is a statement that contradicts its own terms, such that it is false by logical necessity.

ex: "something can come from nothing." Evolutionists commonly disagree with this, but every example of "nothing" that they can give, from which "something" can come, is ''not really nothing.'' It is in fact something, just not understood very well. The evolutionists may be accused of a "non-God of the Gaps" fallacy when they make this claim.

===Conflation===
[[Conflation]] is the logical fallacy of treating two distinct concepts as if they were one.

ex: equivocating goo-to-you evolution with the concept of natural selection. One can be observed, the other cannot.

===Infinite regression===
An [[infinite regression]] results when one asserts that a given event caused another, and yet that first event requires another, identical event, to cause ''it.'' The "cyclic universe" model of the origin of the universe is an example of an infinite regression--for what shall we say caused the first among a never-ending series of explosions?

===Loaded question===
: ''Main Article: [[Loaded question]]''

A loaded question is a question that assumes facts not in evidence, with the intent of trapping the other person into admitting those facts.
ex: "have you stopped beating your wife yet?" Or, as it pertains to Creationists, evolutionists like to say, "why are you lying to children?" or "why do you hate science?" etc. Comment is hardly necessary.

===Special pleading===
: ''Main Article: [[Special pleading]]''

Special pleading means applying to other people a set of standards that one is not willing to apply to oneself, without offering any reasonable grounds for claiming such exemption. [[Jesus Christ]], of course, had a word for this sort of behavior: [[hypocrisy]].

An example of this is the demand that Creationists must publish their pro-God research results in secular (i.e. anti-God) publications, without acquiescing to force all evolutionists to publish in Creationist journals to be considered legitimate.

=== Straw man ===
: ''Main article [[Straw man]]''

This fallacy is where a person argues against an position similar to but weaker than their opponent’s actual position.

Example:
*E. Creationists claim that species are fixed, but not only is there great variety with in [[species]] but species have been observed as coming from other species.
*C: This is a fallacy because Creationists do not claim that species are fixed, but that [[created kind]]s are fixed, with a great amount of variety within those kinds, often leading to many of today's species.

===Bifurcation===
The fallacy of bifurcation is committed when two propositions are presented as if they were mutually exclusive and the only two possibilities, when in fact they are not.<ref name=lisle>{{cite book|author=Lisle, Jason|title=The Ultimate Proof of Creation:Resolving the origins debate|publisher=Master Books|year=2009|page=112|location=Green Forest, AR|isbn=978-0-89051-568-6}}</ref> This fallacy is also know as a "false dilemma".

Example:
*E. Either you live by faith or you are a rational thinker.<ref name=lisle />

===Affirming the consequent===
The Affirming the consequent draws a conclusion from premises that do not support that conclusion by confusing necessary and sufficient conditions. Sarfati examines the fallacy:<ref>{{cite book|author=Sarfati, Jonathan|title=[[The Greatest Hoax on Earth?]]:Refuting Dawkins on Evolution|location=Atlanta, Georgia|publisher=Creation Book Publishers|year=2010|page=75|isbn=978-0-949906-73-1}}</ref>

* Theory T predicts observation O;
* O is observed;
* Therefore T is True

Example:
*:Argument: ''If I eat only burgers I'll get fat; I'm fat; therefore I ate only hamburgers''
*:Problem: Other things, such as thyroid problems, can cause someone to become fat. The argument treats a diet with only hamburgers as a [[necessary condition]] of becoming fat; in fact, a diet with only hamburgers is a [[sufficient condition]] of becoming fat, but it is not necessary to have a diet with only hamburgers for one to becomes fat.

== References ==
<references/>

== Further Reading ==
* [http://www.informationisbeautiful.net/visualizations/rhetological-fallacies/ Rhetological fallacies]
* [http://afterall.net/illogic Illogic Primer]
* [http://apologetics315.blogspot.com/2009/05/logic-primer-5-logical-fallacies.html Logic Primer 5: Logical Fallacies] Brian Auten for Apologetics 315
* [http://www.creationsafaris.com/crevbd.htm The Baloney Detector]
* [http://www.csun.edu/~dgw61315/fallacies.html Logical Fallacies and the Art of Debate]

== See Also ==
* [[Anticreationist debate tactics]]

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