ThéorèmeEn mathématiques et en logique, un théorème (du grec théorêma, objet digne d'étude) est une assertion qui est démontrée, c'est-à-dire établie comme vraie à partir d'autres assertions déjà démontrées (théorèmes ou autres formes d'assertions) ou des assertions acceptées comme vraies, appelées axiomes. Un théorème se démontre dans un système déductif et est une conséquence logique d'un système d'axiomes. En ce sens, il se distingue d'une loi scientifique, obtenue par l'expérimentation.
Subjective logicSubjective logic is a type of probabilistic logic that explicitly takes epistemic uncertainty and source trust into account. In general, subjective logic is suitable for modeling and analysing situations involving uncertainty and relatively unreliable sources. For example, it can be used for modeling and analysing trust networks and Bayesian networks. Arguments in subjective logic are subjective opinions about state variables which can take values from a domain (aka state space), where a state value can be thought of as a proposition which can be true or false.
Material implication (rule of inference)In propositional logic, material implication is a valid rule of replacement that allows for a conditional statement to be replaced by a disjunction in which the antecedent is negated. The rule states that P implies Q is logically equivalent to not- or and that either form can replace the other in logical proofs. In other words, if is true, then must also be true, while if is true, then cannot be true either; additionally, when is not true, may be either true or false.