The appeal to authority (also known as the argument from authority, authority fallacy, appeal to expertise, appeal to expert opinion, and argumentum ad verecundiam) is a logical fallacy that occurs when a claim is assumed to be true because it was made by a perceived authority figure. In addition, the appeal to authority is …
A snuck premise is a controversial and unsupported assumption that someone includes in their argument as if it’s necessarily true. For example, if someone says “the problem with this immoral law is that it will have negative consequences”, the premise that the law is immoral can be considered snuck, if it’s controversial and unsupported …
The post hoc fallacy (from the Latin post hoc ergo propter hoc, meaning “after this, therefore because of this”) is a logical fallacy that occurs when someone assumes that because one event occurred after another, then the second event must have been caused by the first. For example, the post hoc fallacy occurs when someone …
A false premise is an incorrect proposition or assumption that forms the basis of an argument and renders it logically unsound. For example, in the argument “all birds can fly, and penguins can’t fly, so penguins aren’t birds”, the premise that “all birds can fly” is false, since some birds can’t fly, and this …
Circumlocution is the act of saying something using more words than necessary, often with the intent of being vague, evasive, or misleading. For example, a politician might use circumlocution by giving a long and vague response to a question, in order to make it difficult for people to notice that the politician didn’t actually …
The appeal to definition (also known as the argument from dictionary) is a logical fallacy that occurs when someone’s argument is based, in a problematic manner, on the definition of a certain term as it appears in a dictionary or a similar source. The main problem with such arguments is that dictionaries are descriptive in …
Equivocation is the deliberate use of vague or ambiguous language, with the intent of deceiving others or avoiding commitment to a specific stance. For example, when a person is asked a direct yes-or-no question, and gives a vague response that doesn’t answer the question, that person is equivocating. The equivocation fallacy is a logical fallacy …
False equivalence is a logical fallacy where someone incorrectly asserts that two (or more) things are equivalent simply because they share some characteristics, despite there also being substantial differences between them. For example, a false equivalence is saying that cats and dogs are the same animal, since they’re both mammals and have a tail. …
A slippery slope is an argument which claims that an initial action could lead to a chain of events with an extreme result, or that if we treat one case a certain way then we’ll have to treat more extreme cases the same way too. For example, a slippery slope argument might claim that …
A false dilemma (or false dichotomy) is a logical fallacy that occurs when a limited number of options are wrongly presented as being mutually exclusive or the only available options. For example, a false dilemma occurs when someone says that we must choose between options A or B, without mentioning that we can pick …