Propositional Fallacies icon

Propositional Fallacies

formal Fallacy

A propositional fallacy is one where an error in logic takes place due to compound propositions--a proposition is a 'statement'. In order for a compound proposition to have a true value, each component proposition must also be true.

Logic formulas:

Example of Propositional Fallacies

  • William Shatner is Captain Kirk or he is in Miss Congeniality. William Shatner is in Miss Congeniality. Therefore he is not Captain Kirk. It is possible for William Shatner to be in both of these movies (in fact he was).
  • I am going to bed or reading a book. I feel really tired tonight, so I will go to bed. So, I cannot read.It is possible to go to bed, as well as read a book.

Note

Alternative Name: Denying the Antecedent

Books About Logical Fallacies

A few books to help you get a real handle on logical fallacies.

The above book links to Amazon are affiliate links. If you click through and make a purchase, I may get a commission from the sale.

Propositional Fallacies

Extended Explanation

Propositional fallacies are errors in reasoning that occur when the premises of an argument are flawed. In other words, propositional fallacies occur when the statements that are used to support an argument are incorrect or illogical. These fallacies can occur in any type of argument, whether it be a formal logical proof or an everyday conversation.

Types of Propositional Fallacies

There are many different types of propositional fallacies, each with its own unique characteristics and ways of presenting themselves in an argument. Some common types of propositional fallacies include:

Propositional fallacies are common in everyday arguments and can be difficult to identify. However, it is important to be aware of these fallacies in order to make sound and logical arguments. By understanding the different types of propositional fallacies and how they present themselves in arguments, we can avoid making these errors and strengthen the quality of our arguments. Additionally, being aware of propositional fallacies can help us to identify when others are using faulty reasoning and avoid being misled by their arguments.