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Emotionally Charged Language: "Pumping up" a term or premise to make it seem stranger than it is, better than it is, or worse than it is. Such language appears in many examples of the other fallacies in this list, employed to twist the meaning of key terms and ideas by phrasing them in such a way that the reader/hearer focuses on connotation over denotation, feeling over meaning.

Euphemism: "softening" a term or premise to make what is genuinely appalling or outrageous seem commonplace; "cleaning up" usage to make what may offend people seem innocuous (this last is often called Bowdlerization).

Dysphemism: Choosing words so as to make what is rather ordinary appear awful or offensive; the opposite of euphemism.

Platitude / Slogan slinging: Substituting cliches, commonplaces, bits of the conventional wisdom in place of actual thought or argument. Insidious: an argument packed with platitudes can seem persuasive when it really says almost nothing.

Style over Substance: An argument or premise that asks to be accepted because it is beautifully put.

Equivocation: The meaning of a key term or phrase is changed midway through the argument, without the reader's being alerted.

Amphiboly: An element of the argument has two equally valid interpretations, which are not clearly distinguished in the argument, and in which one is carefully substituted for the other without the reader's noticing.

Fallacy of the Accent: Misplaced emphasis on a particular word or phrase used to change the perceived meaning of a sentence.

Failure to Elucidate / Ignotum per Ignotius: The definition or explanation of an idea is just as difficult to understand as the original, so no light is cast. Often happens when a word is defined in terms of other words that are just as unclear. A.k.a. "explaining the obscure by the occult."

Category Error: A category error occurs when two substantive terms (nouns, noun phrases) are used in such a way as to imply that they are generically alike, alike in terms of their proper conceptual category, when, in fact, they are generically different: they are different sorts of things altogether. When performed with verbs, this is a "misleading sylepsis."

Persuasive Definition: A definition of a key term phrased in such a way as to commit the reader to a certain conclusion already; also called circular definition (see also begging the question.)

Slippery Assimilation: Slippery Slope (below) involves an appeal to negative consequences; a slippery assimilation is a series of dubious analogies. Slippery assimilation happens when a certain idea is said to be just like another, slightly more implausible idea, and that, in turn, to a slightly more implausible idea, until a wildly implausible conclusion is reached.

Polishing the apple: Overselling the evidence for a conclusion, when that evidence is in fact weak or dubious, usually in a way that flatters the hearer or advances the particular interests of the speaker.

Provincial Fallacy: Asserting that what is true for us, here, now, is true for everyone at all times and places.

Subjectivist Fallacy: An argument whose premises or conclusions are to be accepted simply because the arguer believes them.

Relativist Fallacy: An argument is accepted or rejected in the face of a decisive contrary argument because the contrary argument is simply taken not to be true for the particular person involved. "That may be true for you, but it is not true for me."

Performative Contradiction: An argument, usually relativist in import, which advances a conclusion that in fact contradicts a necessary but unstated assumption or implicature of the argument form itself. Also called the Ishmael Effect: "and I only am escaped alone to tell thee."

Argument from Silence / Argumentum Ex Silentio: An argument is to be accepted or rejected simply because those who would disagree haven't said anything.

Appeal to Common Sense / Ad Judicium: Another appeal to popularity, in which an argument is supported only because it appeals to our unexamined common sense, or to what "everybody knows."

Appeal to Tradition: Asserting the truth of a conclusion because it has always been taken to be true - "things have always been done this way."

Appeal to the Mean / Fallacy of the Middle Ground: A conclusion is recommended simply because it seems less extreme than proposed alternatives, or because it will appeal to a greater mass of the uncommitted.

Appeal to Novelty: The contrary to the Appeal to Tradition. Arguing a conclusion because of its currency or cachet, or against one on the grounds of its being unfashionable or old.

Appeal to Snobbery/Vanity: A form of the appeal to popularity, in which it is not the "mass" to which we appeal, but some specified subtype said to have desirable traits.

Appeal to Laughter/Ridicule: Satire or ridicule of an opponent's position given in place of a genuine refutation.

Slippery Slope: An argument that a certain thing should not be done, because it will lead inevitably to another slightly worse thing, and that will, in turn, lead to a slightly worse thing, until a really terrible conclusion is reached. Note: Slippery Slopes are not always false.

Appeal to Force or Fear / Ad Baculum: A false appeal to fearful consequences. The conclusion should be accepted because something awful or frightening is threatened if one does not accept it, regardless of its truth.

Appeal to Material Interests / Ad Crumenam: The conclusion is to be accepted because doing so will grant some material reward. Or, a conclusion is to be rejected because otherwise the rejector will lose something dear - blackmail.

Appeal to Pity / Ad Misericordiam: The conclusion should be accepted because of the pity we feel for the person who argues for it or for the sad state of those who are the subjects under discussion.

Tu Quoque (Ad Hominem) / "You too": A version of the Ad Hominem fallacy, in which the opponent's argument is rejected because his own conduct or character is no better than the people he argues against. Attempt to show that an argument is false because it is given in bad faith. Also known as the appeal to hypocrisy.

Poisoning the Well: An ad-hominem attack is given in advance of the argument's being presented, so as to make the audience unsympathetic to it.

Guilt by association: The argument is to be rejected because those who advance it are said to be associated with some evil.

Genetic Fallacy: The conclusion should be accepted because it was originally associated with good things or was proposed by good people, or should be rejected because it was originally associated with bad things or was proposed by bad people.

The Dan Quayle Technique: Suppressing the expectations for an argument in advance, so as to make a weak argument appear stronger by more closely matching our diminished standards.

Straw Man: Refuting a deliberately weakened or distorted version of an opponent's argument, rather than their actual argument.

Improper Burden of Proof: Requiring that one do more (or less) than is really necessary before they are believed; placing an improperly heavy (or light) burden of proof on one's self or on the opposition.

Reductive fallacy: in which a complex argument is reduced to simpler, but misleading terms, which are then refuted. A fallacy of dodgy substitution and paraphrase.

False Dilemma/False Dichotomy: An argument is represented as requiring a choice between two alternatives, where this choice is not required, or these alternatives are not the only ones.

Perfectionist Fallacy: A version of the False Dilemma, in which a workable or effective proposal is rejected because it does not address every conceivable problem, or fails to perfectly address the problem.

Complex Question: A question posed so as to commit the answerer to an unpalatable position, no matter how they answer. Frequently a variant of the False Dilemma.

Sample Too Small: There are not enough members of the sample to make a confident generalization.

Unrepresentative Sample or Improper Stratification: The sample does not accurately represent the nature and proportion of the variability within the target population. In other words, the sample is improperly stratified: it either excludes relevant sub-populations, includes unneeded ones, mixes the sub-populations in improper proportions, or elides the distinctions among subpopulations in a way that biases the data.

Self-Selection: Typically occurs within surveys; the sample was given the choice as to whether or not to respond to the study, and this choice becomes a confounding variable. The sample has selected itself along lines that do not correspond to proper stratification.

Post Hoc (ergo propter hoc): "First this, therefore because of this." To assume that, just because two events are correlated in time, that the prior event thereby causes the posterior.

Accidental Relation: To assume that one event caused a second when, in fact, the two occurred together just by coincidence.

Confusion of Correlation with Cause: To assume that, because two events are known to correlate in a statistical sample, that there is a causal relation between them. The false correlation may occur for any of the reasons contained in the post hoc fallacy.

Hysteron-Proteron: To assume that one event caused a second, when, in fact, the second event caused the first. The "cart before the horse" fallacy, also called wrong direction.

Joint Effect: To assume that one event caused a second, when in fact both events are effects of some other, underlying cause.

Joint Cause: To assume that one event caused a second, when in fact both events are conjunctive causes of some further effect.

Complex Cause / Neglected Cause: To assume that one event, acting alone, caused a second event, when, in fact, that first event was acting in combination with a number of other events to cause the second. To imagine that a necessary condition that is a member of a jointly sufficient set of conditions is a sufficient condition by itself, or to imagine that part of the set of jointly sufficient conditions is all that's needed to produce the effect.

Complex Effect / Neglected Effect: To assume that particular cause brings about only one particular effect, when really that cause necessarily brings about a number of effects that occur together. If the conclusion of a causal argument is inconsistent with or is canceled by one of the neglected effects, the argument can still be false even if the argument asserts a genuine causal relation. Not always a fallacy; sometimes the ignored effects don't matter.

Confounding Variable: The ideal of scientific/statistical methodology is to examine the effects of just one factor at a time; but, outside of laboratory conditions, factors (variables) that might affect the outcome of the study cannot always be controlled in this way. To fail to recognize that a correlation may have been influenced by other, unseen, factors, is to ignore the potential confounding variables.

Insignificance: In a statistical correlation, to assume that, because you've proved some event to be a genuine cause of another, does not allow you to assume that the relation is a strong one. The cause could only be weakly determining, or only produce a mild tendency; the correlation could be insignificant when compared to others. Often, this fallacy goes with the complex cause.

Fallacy of Accident: To treat an accidental or specific property of a particular thing as though it were an essential property of everything of the same kind. [The classic example: the meat you bought yesterday was raw. Today you ate the meat, so today you ate raw meat. The false assumption is that, because some meat was once seen to be raw, all meat everywhere is always raw. A version of stereotyping: "I saw some black panhandlers. All panhandlers are black."] (Latin: argumentum a dicto simpliciter ad dictum secundum quid)

Converse Fallacy of Accident: To treat an essential property of a certain kind of thing as though it were inessential or temporary; to forget or omit in the conclusion of an argument a circumstance or assumption that was essential to the truth of a premise, even if that assumption was only implicit. [Example: assuming that the principles of economics explain everything about human behavior, when those principles only hold on the assumption that people are rational, which they aren't, necessarily. The phrase "all other things being equal [ceteris paribus]" is usually an attempt at avoiding this fallacy.] (Latin: argumentum a dicto secundum quid ad dictum simpliciter.)

Fallacy of Division: To assume that, because a whole, or whole group, has some property, that every individual part or member must have that property.

Fallacy of Composition: To assume that, because all the members of a group or parts of a whole have a property, the whole or the entire group must itself have that property.

Affirming the Consequent: If x is true, then y is also true; we know y is true; therefore x is true also. False, because y could have been true for some other reason; the truth of the consequent doesn't guarantee the truth of the antecedent. Example:

P1)	If Clinton committed a crime, he will be impeached.
P2)	Clinton will be impeached.
C)	Clinton committed a crime.

We cannot validly conclude C, because Clinton could have been impeached for some other reason - partisan politics, for example.

Denying the Antecedent: If x is true, then y is also true; we know x is false; therefore y is also false. False, because y's truth doesn't depend only on the truth of x; the consequent could be true for some other reason. Example:

P1)	If Clinton committed a crime, he will be impeached.
P2)	Clinton did not commit a crime.
C)	Clinton will not be impeached.

We cannot validly conclude C, because Clinton may be impeached despite the fact that he has committed no crime - he may be impeached for partisan political reasons.

Rules for categorical syllogisms:

* The middle term must be fully distributed in at least one premise (that is, one premise must assert or deny some property of every member of the set of things represented by the middle term).

* All terms distributed in the conclusion must be distributed in a premise.

* At least one premise must be affirmative in quality.

* If a syllogism has a negative premise, the conclusion must also be negative; a negative conclusion requires a negative premise.

* A syllogism with two premises universal in quantity ("all" or "none" are or are not) cannot have a conclusion particular in quantity ("some" or "at least one" is or is not).

Fallacies of Categorical Syllogisms:

Four Terms: The syllogism has four terms.

Undistributed Middle: The middle term is fully distributed in neither the major nor the minor premise.

Illicit Major: The major premise is distributed in the conclusion but in neither of the premises.

Illicit Minor: The minor premise is distributed in the conclusion but in neither of the premises.

Fallacy of Exclusive Premises: A syllogism that has two negative premises is fallacious.

Fallacy of Drawing an Affirmative Conclusion From a Negative Premise: One cannot draw an affirmative conclusion when either of the premises is negative.

Existential fallacy: Asserting a conclusion particular in quantity when both premises are universal in quantity.

Confusion of Contrary and Contradictory: Confusing contrary pairs of terms or statements ("white" and "black", or "all trees have leaves" and "no trees have leaves") with contradictory pairs: ("white" and "nonwhite", or "all trees have leaves" and "some trees do not have leaves.") Pairs of contraries cannot both be true or both obtain simultaneously and in the same respect, but both can be false. Pairs of contradictories guarantee the opposite truth value to each member - if one is true, the other must be false, and vice-versa.

Improper Conversion: Improper conversion of an A, E, I or O - form categorical statement into a form with which the original is not logically equivalent; faulty transformation of a statement into its contrary, subcontrary, contradictory, converse, obverse, or contrapositive. Remember that only contraposition guarantees equivalence, and that universal affirmatives can only be partially converted.