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

Example Sentences

Their method, which is based on the formal logic used by mathematicians and philosophers, captures the choices faced by a hacker who has access to the mobile phone and the PIN.

From Science Daily • Jan. 22, 2024

Pinker’s main focus is the sort of conscious, sequential reasoning that can track the steps in a geometric proof or an argument in formal logic.

From Washington Post • Oct. 7, 2021

For interested readers, Budiansky supplies an appendix that moves through Gödel’s proof, step by step, but granular knowledge of formal logic isn’t essential for anyone’s enjoyment of this moving biography.

From New York Times • Jun. 2, 2021

We pay lip service to critical thinking skills, but high schools rarely offer courses in formal logic.

From Slate • Apr. 21, 2015

In formal logic and in mathematics, proof is something absolute.

From "Words Like Loaded Pistols" by Sam Leith