formal logic

American  

noun

1. the branch of logic concerned exclusively with the principles of deductive reasoning and with the form rather than the content of propositions.

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formal logic British  

noun

1. Also called: symbolic logic.  the study of systems of deductive argument in which symbols are used to represent precisely defined categories of expressions Compare philosophical logic

2. a specific formal system that can be interpreted as representing a fragment of natural argument

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Etymology

Origin of formal logic

First recorded in 1855–60