8 Questions
What is the primary concern of logic?
Distinguishing good arguments from bad ones
What branch of logic deals with the study of logical systems using formal languages and mathematical techniques?
Formal Logic
What is an argument with true premises and a valid inference?
Sound argument
What logical operator represents 'not' or negation?
¬
Which rule of inference states that from A and A→B, we can infer B?
Modus Ponens
Who developed the syllogism?
Aristotle
What is the term for an error in reasoning that makes an argument invalid or unsound?
Fallacy
What is the term for the process of drawing a conclusion from one or more premises?
Inference
Study Notes
Logic
Definition
- The study of reasoning, argumentation, and inference
- Concerned with the principles and methods of distinguishing good arguments from bad ones
Branches of Logic
- Formal Logic: Deals with the study of logical systems, using formal languages and mathematical techniques
- Informal Logic: Focuses on the study of natural language arguments and everyday reasoning
- Philosophical Logic: Examines the philosophical foundations of logic, including the nature of truth, validity, and inference
Key Concepts
- Argument: A set of statements, one of which is the conclusion, and the others are the premises
- Validity: An argument is valid if its conclusion follows logically from its premises
- Soundness: An argument is sound if it is both valid and has true premises
- Inference: The process of drawing a conclusion from one or more premises
- Fallacy: An error in reasoning that makes an argument invalid or unsound
Logical Operators
- Negation (¬): Not, negates a statement
- Conjunction (∧): And, combines two statements
- Disjunction (∨): Or, combines two statements
- Material Implication (→): If-then, implies a conditional relationship
- Biconditional (): If and only if, implies a necessary and sufficient condition
Rules of Inference
- Modus Ponens (MP): From A and A→B, infer B
- Modus Tollens (MT): From A→B and not B, infer not A
- Hypothetical Syllogism (HS): From A→B and B→C, infer A→C
Famous Logicians
- Aristotle: Ancient Greek philosopher who developed the syllogism
- Gottlob Frege: German philosopher and logician who developed modern formal logic
- Bertrand Russell: British philosopher and logician who worked on type theory and propositional logic
Logic
Definition
- The systematic study of reasoning, argumentation, and inference to distinguish good arguments from bad ones
Branches of Logic
- Formal Logic: Studies logical systems using formal languages and mathematical techniques
- Informal Logic: Focuses on natural language arguments and everyday reasoning
- Philosophical Logic: Examines the philosophical foundations of logic, including truth, validity, and inference
Key Concepts
- Argument: A set of statements with one conclusion and one or more premises
- Validity: An argument is valid if its conclusion logically follows from its premises
- Soundness: An argument is sound if it is valid and has true premises
- Inference: The process of drawing a conclusion from one or more premises
- Fallacy: An error in reasoning that makes an argument invalid or unsound
Logical Operators
- Negation (¬): Not, negates a statement
- Conjunction (∧): And, combines two statements
- Disjunction (∨): Or, combines two statements
- Material Implication (→): If-then, implies a conditional relationship
- Biconditional (): If and only if, implies a necessary and sufficient condition
Rules of Inference
- Modus Ponens (MP): From A and A→B, infer B
- Modus Tollens (MT): From A→B and not B, infer not A
- Hypothetical Syllogism (HS): From A→B and B→C, infer A→C
Famous Logicians
- Aristotle: Developed the syllogism
- Gottlob Frege: Developed modern formal logic
- Bertrand Russell: Worked on type theory and propositional logic
Test your understanding of the principles and methods of distinguishing good arguments from bad ones, including formal logic, informal logic, and philosophical logic.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free