Geometry as a Measurement-Theoretical A Priori: Lorenzen's Defense of Relativity Against the Ontology of Its Proponents.

Lorenzen rejects ontological commitments of relativity. Realism of physical geometry Geometry already breaks down with Poincaré's arguments. Lorenzen agrees with Poincaré, but offers a constructive account: space is not an empirical Empirical entity described by means of conventions Convention , but a purely constructive entity constituted by the norms of spatial measurement Measurement . This space however, as Lorenzen argues, is Euclidean. In this paper, we shall analyse Lorenzen arguments and explicate how they relate to arguments from empiricism Empiricism and neo-kantianism. It will be shown that the originality of Lorenzen's position consists in systematically accounting for the role of measurement and measurement instruments. [ABSTRACT FROM AUTHOR]