What is a fallacy?
A logical fallacy is a mistake in reasoning. Logical fallacies are tricks or mistakes in reasoning intended to persuade someone to agree with an argument that is unreasonable either because it is not logical or because the reasons are untrue.
Two Genres of Fallacies:
There are numerous ways that an argument can be unreasonable, and as a result the list of all potential fallacy categories can appear endless. In order to support awareness around unreasonableness, this website describes and illustrates the most popular fallacies found in every day life. To help with understanding these various fallacies, we can first start by understanding the three general categories of fallacies that all types of fallacies are a part of:
Arguments can sometime be confusing because they contain ambiguous words or phrases whose meanings shift and change throughout the argument. Often when reasons only appear to support the conclusion, this is due to ambiguity. Vagueness or manipulation in language can cause an argument to become a fallacy of ambiguity. We often do not notice subtle manipulations in language and are therefore mislead to believe the argument.
To determine if an argument is an Ambiguity Fallacy, ask yourself:
- Is something unclear?
- Are words or phrases being used differently throughout the argument?
In order for an argument to be true, the reasons have to directly support the conclusion. When the reasons are not connected to the conclusion, and are therefore irrelevant to the truth of the conclusion, the argument becomes a fallacy of relevancy. Often these reasons are true but have nothing to do with the position being argued. We often tend to find these types of fallacious arguments convincing because the reasons are reasonable and perhaps not obviously irrelevant.
To determine if an argument is a Relevancy Fallacy, ask yourself:
- Is something irrelevant within the argument?
- Do the reasons have anything to do with the conclusion?
Assumptions are thoughts or beliefs that we believe to be true even though they have not properly be tested and verified as true. Since assumptions are a part of our everyday lives, we often do not notice when they are used in arguments. When an argument is assuming something to be true that is not necessarily true in order to establish a particular conclusion, the argument becomes a fallacy of presumption. If an argument is based on false reasons, then we cannot guarantee that the conclusion is true.
To determine if an argument is a Presumption Fallacy, ask yourself:
- Is something being assumed?
- Are reasons one of claiming something as fact when it really should?