Tensed Logic of Science
This paper brings together two debates, wich are interrelated content wise, but have had (virtually) no impact on each other. In contemporary philosophy of time the debate between so called tensed and tenseless theory is one of the main issues. Arthur Prior has famously argued that reference to the present moment is both important for our actions and not translatable without loss of meaning into just tenseless concepts and sentences. This argument has been much contested since and the sufficiency of a tenseless theory is open to controversy up until today. Independent of this the status of indexical concepts for Rudolf Carnap’s logic of science has been subject to philosophical analysis. It his hard to pin down Carnap’s position on the importance of indexicality − and thus reference to the present moment − since there is a certain tension in his own writings. His early work up until ‚Der logische Aufbau der Welt‘ differs in some important points from ideas he develops in ‚Testability and Meaning‘ or his two level conception. So the first goal of this paper is a reconstruction of Carnap’s thoughts on tense regarding the language of science. I will access not only Carnap’s own Œvre but also contrast him with other coeval philosophers, especially Otto Neurath and Carl Gustav Hempel. The second goal then goes beyond Carnap: I will argue for a tensed theory, i.e. I will try to show that it is not possible to translate tensed sentences, which are located at the core of scientific language, into tenseless counterparts without loss of meaning. I claim that tensed sentences and beliefs are needed (in the style of an transcendental argument) to anchor the tenseless physical relation of earlier/later. To do so, I will borrow an argument which Carnap himself gives in the context of measuring procedures.