Definition of formal logic in US English:

formal logic


  • Logic based on argument involving deductively necessary relationships and including the use of syllogisms and mathematical symbols.

    • ‘Dating all the way back to the ancient world, the study of logic historically focused on how to tell a good argument from a bad one, where formal logic provided techniques for testing the validity of arguments.’
    • ‘It is not much of an exaggeration to state that the semantics and deductive systems for formal logic have become the lingua franca throughout the issues and concerns of contemporary philosophy.’
    • ‘They wish, like Leibniz, to put all true statements on a level with those of formal logic or pure mathematics; or, like the existentialists, they attach a tragic significance to the fact that this cannot be done.’
    • ‘Other questions can be answered deductively, by referring to established rules; this is the case, for example, with mathematics, grammar and formal logic.’
    • ‘Several series of larger drawings from the 1980s seem to derive formal logic from the small ones that precede them, grouped by his signature iconographic devices.’
    • ‘The new curriculum assumes that thinking presupposes formal logic, but it does not explain how one acquires it; so, in practice, the new curriculum assumes that formal logic is innate.’
    • ‘What Parmenides did was to apply logic to the arguments of the Pythagoreans, thus setting the groundwork of formal logic.’
    • ‘There has been a large amount of modern discussion as to what Aristotelian deductions are, in terms of modern formal logic, and hence as to how his logic should be classified.’
    • ‘As an aside, I can remember about twenty years ago how I benefited greatly from a study of formal logic which covered the subjects of the structure of language and the meaning of words.’
    • ‘‘His interpretation of Christianity is far too external and too dependent on formal logic,’ he said.’
    • ‘Unlike other Hellenistic schools, such as those of Aristotle and the Stoics, the Epicureans were not greatly interested in formal logic, but they certainly needed a theory of the formation of beliefs.’
    • ‘For this reason, deductive arguments are usually limited to inferences that follow from definitions, mathematics and rules of formal logic.’
    • ‘Doesn't the author himself, while ‘rejecting’ the formal logic, proceed from the formal logic's law of excluded middle?’
    • ‘Although other and subsequent forms of analysis, such as linguistic analysis, were less wedded to systems of formal logic, the central insight motivating logical analysis remained.’
    • ‘You mean that no one ever does write a proof down in formal logic?’
    • ‘Meanwhile, a commander, as he addresses some or other control problem, is based not only on rules of formal logic but a process of combat operations as a whole, complete with its indeterminacy and contradictoriness.’
    • ‘However, the rationality that is implied by formal logic is more aptly viewed not as a characteristic of an individual but as a property of the problem-situation in which an individual reaches a decision.’
    • ‘Trotsky used the metaphor of elementary and higher mathematics to explain the relationship between formal logic and dialectic logic.’
    • ‘Although Google runs on a nutrient medium of von Neumann processors, with multiple layers of formal logic as a base, the higher-level meaning is essentially statistical in character.’
    • ‘The reduction of proofs to an algebraic calculus by means of formal logic would allow one to decide which of two given proofs is simpler merely by comparing the number of operations involved in each.’