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Formal logic is the study of inference conducted with purely formal content, where the validity of an argument depends solely on its logical form rather than on the meaning of its...
A syllogism is a classical form of deductive reasoning consisting of two premises and a conclusion, typically organized around a major premise, a minor premise, and a final claim....
Propositional logic operates on whole propositions—that is, statements that are either true or false—and combines them using logical connectives. A truth table is a mathematical to...
Propositional logic supplies a set of rules of inference—reliable patterns for deriving conclusions from premises. Modus ponens reasons from \(P \to Q\) and P to Q. Modus tollens r...
Fallacies are errors in reasoning that undermine arguments, and they come in two broad kinds. Formal fallacies arise from invalid logical form; informal fallacies arise from proble...
The scientific method provides a systematic framework for testing claims about the world: observation leads to questions, which generate hypotheses, which are tested by experiment,...
Human reasoning is systematically shaped by cognitive biases, mental shortcuts, and predictable errors that can distort even careful thinking. Confirmation bias leads us to search...
Predicate logic, also called first-order logic, extends propositional logic with quantifiers and predicates, allowing statements about properties of objects and relations among the...