rule

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rule

1. the exercise of governmental authority or control
2. the period of time in which a monarch or government has power
3. a prescribed method or procedure for solving a mathematical problem, or one constituting part of a computer program, usually expressed in an appropriate formalism
4. any of various devices with a straight edge for guiding or measuring; ruler
5. Christianity a systematic body of prescriptions defining the way of life to be followed by members of a religious order
6. Law an order by a court or judge

Rule

 

a proposition that expresses permission or a requirement to perform or refrain from performing, under particular conditions, some act; the word “act” is understood to refer to some action or absence of action. These rules are called rules of permission and obligation, respectively; they are considered in a natural way to be elementary, or rules of the first rank, and are subsumed under the general term “injunction.” Complex rules are rules of the (n+ 1)th rank, obtained by applying injunctions to collections of rules of the nth or lesser rank in such a way that at least one of these rules must be of the nth rank. Ordinary grammatical rules are examples of rules of different, but not very high, ranks. A method is a system of rules of different ranks that includes rules designating the order in which other rules of the same system are introduced and rearranged.

Rules, whose systematic study is the object of deontic (normative) logic, are of importance in daily life and in all branches of science, particularly mathematics, logic, linguistics, ethics, jurisprudence, sociology, and political economy.

rule

[rül]
(mathematics)
An antecedent condition and a consequent proposition that can support deductive processes.

Rule

[′rül]
(astronomy)

rule

common types of rules
An instrument having straight edges, usually marked off in inches or centimeters and fractions thereof; used for measuring distance and for drawing straight lines.
References in periodicals archive ?
CANCER RESEARCH UK advise using the ABCD rule to check moles for signs of melanoma: * ASYMMETRY: the two halves of your mole do not look the same.
Often moles can become itchy or begin to weep but the charity advises people to use the ABCD rule to spot early warning signs.
The ugly duckling--the outlier, the exceptional nevus, the one that looks different from the others--is more likely to be a melanoma, even if it does not exhibit the classic features ascribed to melanoma in the ABCD rule.