References
- (Wikipedia, 2009) ⇒ http://en.wikipedia.org/wiki/Logic
- Logic is the study of the principles of valid demonstration and inference. Logic is a branch of philosophy, a part of the classical trivium.
- The word derives from Greek λογική (logike), fem. of λογικός (logikos), "possessed of reason, intellectual, dialectical, argumentative", from λόγος logos, "word, thought, idea, argument, account, reason, or principle".
- Logic concerns the structure of statements and arguments, in formal systems of inference and natural language. Topics include validity, fallacies and paradoxes, reasoning using probability and arguments involving causality. Logic is also commonly used today in argumentation theory.

- http://en.wiktionary.org/wiki/logic
- logic (countable and uncountable; plural logics)
- 1. (uncountable) A method of human thought that involves thinking in a linear, step-by-step manner about how a problem can be solved. Logic is the basis of many principles including the scientific method.
- 2. (philosophy, logic) The study of the principles and criteria of valid inference and demonstration.
- 3. (uncountable) (mathematics) The mathematical study of relationships between rigorously defined concepts and of proof of statements.
- 4. (countable) (mathematics) A formal or informal language together with a deductive system or a model-theoretic semantics.
- 5. (uncountable) Any system of thought, whether rigorous and productive or not, especially one associated with a particular person.
*It's hard to work out his system of logic.*
- 6. (uncountable) The part of an electronic system that performs the boolean logic operations, short for logic gates or logic circuit.
*Fred is designing the logic for the new controller.*

- Synonyms
- (mathematics, study): formal logic, modern logic
- (mathematics, system): formal system
- (philosophy): predicate logic

- http://mcckc.edu/longview/ctac/glossary.htm
- Logic: Definition: The study of the principles of rational inference.