often interpreted meaning higher order logic brings form platonism ie view universal properties relations exist addition individuals ref name cambridge ref name ketland deviant logics intuitionistic intuitionistic logic restricted version classical logic ref name moschovakis ref ref name burgess ref ref name macmillannonclassical restricted sense certain rules inference used classical logic constitute valid inferences concerns specifically law excluded middle double negation elimination ref name moschovakis ref name burgess ref name macmillannonclassical law excluded middle states every sentence either
Humanities Philosophy Logic Philosophical logic