- An example of logic is deducing that two truths imply a third truth.
- An example of logic is the process of coming to the conclusion of who stole a cookie based on who was in the room at the time.

## logic

- the branch of philosophy dealing with correct reasoning, describing relationships among propositions in terms of implication, contradiction, contrariety, conversion, etc.
- a particular system of such relationships: Aristotelian
*logic*

- correct reasoning; valid induction or deduction: the lack of
*logic*in his scheme - way of reasoning, whether correct or incorrect: to use faulty
*logic* - the system of principles underlying any art or science
- necessary connection or outcome, as through the working of cause and effect: the
*logic*of events - the systematized interconnection of switching functions, circuits, or devices, as in electronic computers

Origin of logic

Middle English*logike*from Old French

*logique*from Classical Latin

*logica*from Classical Greek

*logik?*(

*techn?*), logical (art) from

*logikos*, of speaking or reasoning from

*logos*, a word, reckoning, thought from

*legein*, to speak, choose, read from Indo-European base an unverified form

*le?-*, to gather from source Classical Latin

*legere*, to collect, Old English

*læce*, leech

## logic

noun

- The study of the principles of reasoning, especially of the structure of propositions as distinguished from their content and of method and validity in deductive reasoning.
**a.**A system of reasoning:*Aristotle's logic.***b.**A mode of reasoning:*By that logic, we should sell the company tomorrow.***c.**The formal, guiding principles of a discipline, school, or science.- Valid reasoning:
*Your paper lacks the logic to prove your thesis.* - The relationship between elements and between an element and the whole in a set of objects, individuals, principles, or events:
*There's a certain logic to the motion of rush-hour traffic.* -
*Computers***a.**The nonarithmetic operations performed by a computer, such as sorting, comparing, and matching, that involve yes-no decisions.**b.**Computer circuitry.**c.**Graphic representation of computer circuitry.

Origin of logic

Middle English*from*Old French

*logique*

*from*Latin

*logica*

*from*Greek

*logikē (tekhnē)*

*(art) of reasoning, logic*

*feminine of*

*logikos*

*of reasoning*

*from*

*logos*

*reason*; see

*leg-*in Indo-European roots.

## logic

See also argumentation; mathematics; philosophy; thinking; truth and error.

a posteriori the process of reasoning from effect to cause, based upon observation.**apriorism**

**1.**the method of a priori reasoning, i.e., deductive reasoning, from cause to effect or from the general to the particular.

**2.**an a priori principle. Barbara a mnemonic word to represent a syllogistic argument in the first figure, in which there are two universal affirmative premises and a universal affirmative conclusion.

**Barmalip, Bramantip**a mnemonic word to represent a syllogistic argument in the fourth figure, in which there are two universal affirmative premises and a particular affirmative conclusion.

**Baroco**a mnemonic word to represent a syllogistic argument in the second figure, in which there is one universal affirmative and one particular negative premise and a particular negative conclusion.

**Bocardo**a mnemonic word to represent a syllogistic argument in the third figure, in which there is one particular negative and one universal affirmative premise and a particular negative conclusion.

**Camestres**a mnemonic word to represent a syllogistic argument in the second figure, in which there is one universal affirmative and one universal negative premise and a universal negative conclusion.

**Celarent**a mnemonic word to represent a syllogistic argument in the first figure, in which there is one universal negative and one universal affirmative premise and a universal negative conclusion.

**Cesare**a mnemonic word to represent a syllogistic argument in the second figure, in which there is one universal negative and one universal affirmative premise and a universal negative conclusion.

**Darapti**a mnemonic word to represent a syllogistic argument in the third figure, in which there are two universal affirmative premises and a particular affirmative conclusion.

**Darii**a mnemonic word to represent a syllogistic argument in the first figure, in which there is one universal affirmative and one particular affirmative premise and a particular affirmative conclusion.

**Datisi**a mnemonic word to represent a syllogistic argument in the third figure, in which there is one universal affirmative and one particular affirmative premise and a particular affirmative conclusion. definiendum

**1.**an expression that has to be defined in terms of a previously defined expression.

**2.**anything that has to be defined. —

**definienda**, n., pl.

**Dimaris**Dimatis.

**Dimatis**a mnemonic word to represent a syllogistic argument in the fourth figure, in which there is one universal affirmative and one affirmative premise and a particular affirmative conclusion. Also called

**Dimaris**.

**Disamis**a mnemonic word to represent a syllogistic argument in the third figure, in which there is one particular affirmative and one universal affirmative premise and a particular affirmative conclusion. elenchus a syllogistic argument that refutes a proposition by proving the direct opposite of its conclusion. —

**elenchic, elenctic**, adj.

**epicheirema**a syllogism in which the truth of one of the premises is confirmed by an annexed proposition (prosyllogism), thus resulting in the formation of a compound argument. See also

**prosyllogism**. equipollence, equipollency equality between two or more propositions, as when two propositions have the same meaning but are expressed differently. See also agreement.

**Felapton**a mnemonic word to represent a syllogistic argument in the third figure, in which there is one universal negative and one universal affirmative premise and a particular negative conclusion.

**Ferio**a mnemonic word to represent a syllogistic argument in the first figure, in which there is one universal negative and one particular affirmative premise and a particular negative conclusion.

**Feriso**a mnemonic word to represent a syllogistic argument in the third figure, in which there is one universal negative and one particular affirmative premise and a particular negative conclusion. Also

**Ferison**.

**Ferison**Feriso.

**Fesapo**a mnemonic word to represent a syllogistic argument in the fourth figure, in which there is one universal negative and one universal affirmative premise and a particular negative conclusion.

**Festino**a mnemonic word to represent a syllogistic argument in the second figure, in which there is one universal negative and one particular affirmative premise and a particular negative conclusion.

**Fresison**a mnemonic word to represent a syllogistic argument in the fourth figure, in which there is one universal negative and one particular affirmative premise and a particular negative conclusion.

**metalogic**the metaphysics or metaphysical aspects of logic. —

**metalogical**, adj. methodology a division of logic devoted to the application of reasoning to science and philosophy. See also classification; order and disorder. —

**methodological**, adj.

**polylemma**a multiple dilemma or one with many equally unacceptable alternatives; a difficult predicament.

**prosyllogism**a syllogism connected with another in such a way that the conclusion of the first is the premise of the one following. schematism the form or character of a syllogism. sorites an elliptical series of syllogism, in which the premises are so arranged that the predicate of the first is the subject of the next, continuing thus until the subject of the first is united with the predicate of the last. —

**soritical, soritic**, adj. syllogism a form of reasoning in which two propositions or premises are stated and a logical conclusion is drawn from them. Each premise has the subject-predicate form, and each shares a common element called the middle term.

**syntheticism**the principles or practice of synthesis or synthetic methods or techniques, i.e., the process of deductive reasoning, as from cause to effect, from the simple elements to the complex whole, etc.

## logic

(*countable and uncountable*, *plural* logics)

- (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.
- (philosophy, logic) The study of the principles and criteria of valid inference and demonstration.
- (uncountable, mathematics) The mathematical study of relationships between rigorously defined concepts and of proof of statements.
- (countable, mathematics) A formal or informal language together with a deductive system or a model-theoretic semantics.
- (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.*

- (uncountable) The part of a system (usually electronic) that performs the boolean logic operations, short for logic gates or logic circuit.
*Fred is designing the logic for the new controller.*

(*third-person singular simple present* logics, *present participle* logicking, *simple past and past participle* logicked)

- (intransitive, pejorative) To engage in excessive or inappropriate application of logic.
- To apply logical reasoning to.
- To overcome by logical argument.

From Old French *logike*, from Latin *logica*, from Ancient Greek *Î»Î¿Î³Î¹ÎºÎ®* (logike, “logic"), from properly feminine of *Î»Î¿Î³Î¹ÎºÏŒÏ‚* (logikÃ³s, “of or pertaining to speech or reason or reasoning, rational, reasonable"), from *Î»ÏŒÎ³Î¿Ï‚* (logos, “speech, reason").

## logic - Computer Definition

The sequence of operations performed by hardware or software. It is the computer's "intelligence." Hardware logic is contained in the electronic circuits and follows the rules of Boolean logic. Software logic (program logic) is contained in the placement of instructions written by the programmer. Software logic is called "business logic" when it refers to the transactions of the business rather than underlying infrastructure such as the operating system, database management system (DBMS) or network.
**Logic Is Not Logical**
The term "logic" is not the same as "logical." Logic refers to algorithms and operational sequences; whereas, "logical" refers to a higher-level view of hardware, software or data that is not tied to physical structures (see logical vs. physical). See also logical expression.