Rachunek nazw i pojęcie pary uporządkowanej

There are various definitions of an ordered pair, from the one with fixing elements (Hausdorff) to the commonly functioning one given by Kuratowski. A definition (with fixing elements) of a tuple is proposed here, in which an ordered pair is a special case within the framework of elementary ontology (OE). Further, the logical status of this kind of definition is analysed. As a contrast, by enriching elementary ontology with Frege's predication scheme (OEsub), a definition of an ordered pair after the manner of Kuratowski is arrived at as well. A definition of the operation of Cartesian multiplication within the framework of this calculus is also given.