The Fallacy of Exclusive Premises is a type of logical error that occurs when someone mistakenly concludes a statement from two or more premises that are mutually exclusive. Example: “Either John is a doctor or he is an engineer.” (Exclusive premise 1)“John is not a doctor.” (Exclusive premise 2)“Therefore, John must be an engineer who […]

The Affirmative Conclusion from a Negative Premise (also known as Illicit Negative) is a type of logical error that occurs when someone mistakenly concludes an affirmative statement from one or more negative premises. Example: “Nobody knows the answer to this question.” (Negative premise)“Therefore, John knows the answer.” (Affirmative conclusion) In this example, the argument starts […]

The Existential Fallacy is a type of logical error that occurs when someone mistakenly assumes that because something exists or has existed, it must have always existed or will continue to exist. Example: “Because some people have always been poor, poverty must be an inherent and eternal aspect of human society.” (Existential Fallacy) In this […]

The Denying the Antecedent is a type of logical error that occurs when someone mistakenly assumes that because the antecedent (the “if” part) of a conditional statement is false, the consequent (the “then” part) must also be false. Example: “If it rains, the streets will be wet.” (Conditional statement)“It didn’t rain.”“Therefore, the streets are not […]

The Affirming the Consequent is a type of logical error that occurs when someone mistakenly assumes that because a conditional statement (if-then) has a true consequent (the “then” part), the antecedent (the “if” part) must also be true. Example: “If it rains, the streets will be wet.” (Conditional statement)“The streets are indeed wet.”“Therefore, it must […]

Logic refers to the systematic study of reasoning and argumentation, encompassing various methods for evaluating arguments, identifying patterns of valid reasoning, and distinguishing between sound and unsound conclusions. It involves the use of logical operators, rules of inference, and formal systems to analyze and evaluate statements, propositions, and arguments. Key Aspects of Logic: Branches of […]

The Affirming the Disjunct is a type of logical error that occurs when someone mistakenly assumes that one part of a disjunction (an “or” statement) being true means that the entire disjunction must be true. This fallacy gets its name from the fact that affirming one disjunct is not sufficient to prove the truth of […]

The Masked-Man Fallacy is a type of logical error that occurs when someone tries to prove an identity or relationship by citing similarities between two entities, without actually providing evidence for their conclusion. This fallacy gets its name from the classic example: Example: Socrates encounters a man wearing a mask and asks him who he […]

The Conjunction Fallacy is a cognitive error that occurs when people overestimate the probability of two events occurring together, compared to the probability of each event occurring separately. This fallacy arises from our tendency to neglect the concept of joint probability and instead rely on intuitive, narrative-based thinking. Example 1: Linda is a woman who […]

The Base Rate Fallacy is a type of cognitive error that occurs when people ignore or neglect to consider the base rate (or prior probability) of an event when making judgments or decisions. This fallacy leads individuals to overestimate the importance of specific information or evidence, while underestimating the impact of general trends or probabilities. […]