Logic, from the Greek λογικός (logikos) is the study of reasoning. Logic is used in most intellectual activity, but is studied primarily in the disciplines of philosophy, mathematics, and computer science. Logic examines general forms which arguments may take, which forms are valid, and which are fallacies. It is one kind of critical thinking. In philosophy, the study of logic falls in the area of epistemology, which asks: "How do we know what we know?" In mathematics, it is the study of valid inferences within some formal language.

As a discipline, logic dates back to Aristotle, who established its fundamental place in philosophy. The study of logic is part of the classical trivium.

Averroes defined logic as "the tool for distinguishing between the true and the false"; Richard Whately, '"the Science, as well as the Art, of reasoning"; and Frege, "the science of the most general laws of truth". The article Definitions of logic provides citations for these and other definitions.

Logic is often divided into two parts, inductive reasoning and deductive reasoning. The first is drawing general conclusions from specific examples, the second drawing logical conclusions from definitions and axioms. A similar dichotomy, used by Aristotle, is analysis and synthesis. Here the first takes an object of study and examines its component parts, the second considers how parts can be combined to form a whole.

Logic is also studied in argumentation theory.

Quotes about logic, rationality, and logical fallacies.

Contents

• 1 Sourced
  • 1.1 Logic and rationality
  • 1.2 Logical fallacies
    • 1.2.1 Appeal to authority
• 2 Unsourced
• 3 External links

Sourced

Logic and rationality

• Logic is a systematic method of coming to the wrong conclusion with confidence.
  • murphy's law

• Logic hasn't wholly dispelled the society of witches and prophets and sorcerers and soothsayers.
  • Raymond F. Jones, The Non-Statistical Man

• Logic is a large drawer, containing some useful instruments, and many more that are superfluous. A wise man will look into it for two purposes, to avail himself of those instruments that are really useful, and to admire the ingenuity with which those that are not so, are assorted and arranged.
  • Charles Caleb Colton, Lacon

• Logic is logic. That's all I say.
  • Oliver Wendell Holmes, The One-Hoss Shay

• Logic is one thing and commonsense another.
  • Elbert Hubbard, The Note Book (1927)

• The want of logic annoys. Too much logic bores. Life eludes logic, and everything that logic alone constructs remains artificial and forced.
  • André Gide

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Mon Jan 25 23:39:03 2010