Ad hominem, short for argumentum ad hominem, is a term that refers to several types of arguments, most of which are fallacious. Typically this term refers to a rhetorical strategy where the speaker attacks the character, motive, or some other attribute of the person making an argument rather than attacking the substance of the argument itself. This avoids genuine debate by creating a diversion to some irrelevant but often highly charged issue. The most common form of this fallacy is "A makes a claim x, B asserts that A holds a property that is unwelcome, and hence B concludes that argument x is wrong".
Argument from ignorance, also known as appeal to ignorance, is a fallacy in informal logic. It asserts that a proposition is true because it has not yet been proven false or a proposition is false because it has not yet been proven true. This represents a type of false dichotomy in that it excludes the possibility that there may have been an insufficient investigation to prove that the proposition is either true or false. It also does not allow for the possibility that the answer is unknowable, only knowable in the future, or neither completely true nor completely false. In debates, appealing to ignorance is sometimes an attempt to shift the burden of proof. The term was likely coined by philosopher John Locke in the late 17th century.
Argumentum ad baculum is the fallacy committed when one makes an appeal to force to bring about the acceptance of a conclusion. One participates in argumentum ad baculum when one emphasizes the negative consequences of holding the contrary position, regardless of the contrary position's truth value—particularly when the argument-maker himself causes those negative consequences. It is a special case of the appeal to consequences.
A fallacy is the use of invalid or otherwise faulty reasoning in the construction of an argument which may appear to be a well-reasoned argument if unnoticed. The term was introduced in the Western intellectual tradition by the Aristotelian De Sophisticis Elenchis.
Appeal to tradition is a claim in which a thesis is deemed correct on the basis of correlation with past or present tradition. The appeal takes the form of "this is right because we've always done it this way", and is a logical fallacy. The opposite of an appeal to tradition is an appeal to novelty, in which one claims that an idea is superior just because it is new.
Poisoning the well is a type of informal fallacy where adverse information about a target is preemptively presented to an audience, with the intention of discrediting or ridiculing something that the target person is about to say. Poisoning the well can be a special case of argumentum ad hominem, and the term was first used with this sense by John Henry Newman in his work Apologia Pro Vita Sua (1864). The etymology of the phrase lies in well poisoning, an ancient wartime practice of pouring poison into sources of fresh water before an invading army, to diminish the invading army's strength.
An appeal to fear is a fallacy in which a person attempts to create support for an idea by attempting to increase fear towards an alternative. An appeal to fear is related to the broader strategy of fear appeal and is a common tactic in marketing, politics, and media (communication).
Appeal to consequences, also known as argumentum ad consequentiam, is an argument that concludes a hypothesis to be either true or false based on whether the premise leads to desirable or undesirable consequences. This is based on an appeal to emotion and is a type of informal fallacy, since the desirability of a premise's consequence does not make the premise true. Moreover, in categorizing consequences as either desirable or undesirable, such arguments inherently contain subjective points of view.
Ad nauseam is a Latin term for an argument or other discussion that has continued to the point of nausea. For example, "this has been discussed ad nauseam" indicates that the topic has been discussed extensively and those involved have grown sick of it. The fallacy of dragging the conversation to an ad nauseam state in order to then assert one's position as correct due to it not having been contradicted is also called argumentum ad infinitum and argument from repetition.
Argument to moderation —also known as false compromise, argument from middle ground, and the golden mean fallacy—is the fallacy that the truth is supposedly always a compromise between two opposing positions. An example would be to regard two opposed arguments, with one person (correctly) saying that the sky is blue and another saying that the sky is in fact yellow, and incorrectly conclude that the sky is the intermediate colour of green.
Argument from fallacy is the formal fallacy of analyzing an argument and inferring that, since it contains a fallacy, its conclusion must be false. It is also called argument to logic, the fallacy fallacy, the fallacist's fallacy, and the bad reasons fallacy.
The following outline is provided as an overview of and topical guide to public relations:
Reductio ad Hitlerum, also known as playing the Nazi card, is an attempt to invalidate someone else's argument on the basis that the same idea was promoted or practised by Adolf Hitler or the Nazi Party. Arguments can be termed reductio ad Hitlerum if they are fallacious. Contrarily, straightforward arguments critiquing specifically fascist components of Nazism like Führerprinzip are not part of the association fallacy.
Proof by assertion, sometimes informally referred to as proof by repeated assertion, is an informal fallacy in which a proposition is repeatedly restated regardless of contradiction and refutation. The proposition can sometimes be repeated until any challenges or opposition cease, letting the proponent assert it as fact, and solely due to a lack of challengers. In other cases, its repetition may be cited as evidence of its truth, in a variant of the appeal to authority or appeal to belief fallacies.
Robert Henry Thouless was an English psychologist and parapsychologist. He is best known as the author of Straight and Crooked Thinking, which describes flaws in reasoning and argument.
Appeal to the stone, also known as argumentum ad lapidem, is a logical fallacy that dismisses an argument as untrue or absurd. The dismissal is made by stating or reiterating that the argument is absurd, without providing further argumentation. This theory is closely tied to proof by assertion due to the lack of evidence behind the statement and its attempt to persuade without providing any evidence.
In argumentation theory, an argumentum ad populum is a fallacious argument which is based on claiming a truth or affirming something is good because the majority thinks so.
An argument from authority, also called an appeal to authority, or argumentum ad verecundiam, is a form of argument in which the opinion of an authority on a topic is used as evidence to support an argument. Some consider that it is used in a cogent form if all sides of a discussion agree on the reliability of the authority in the given context, and others consider it to be a fallacy to cite the views of an authority on the discussed topic as a means of supporting an argument.
