Gerhard Tintner: Oral Reply in Discussion on Professor Tintner’s Paper (1949)

This brief oral reply addresses one issue raised by Professor Bartlett: the relationship between probability₁ and probability₂. Tintner reserves most responses for writing, concentrating here on how the two concepts can remain distinct while being related. His central claim is that conceptual clarity, rather than agreement on a single account of probability, is necessary for productive discussion.

It seemed to him that in a great many of the discussions the confusion did not arise so much because people held different views about probability, but because they did not make a clear distinction between the two concepts.

Tintner explains Carnap’s emphasis on differences as serving the purpose of bringing out the contrast between the concepts. Yet distinction does not imply isolation: probability₁ can also apply to statements about probability₂. The reply then moves from this relationship to a requirement connecting inductive inference with relative frequency:

Any system of inductive inference must have this property, that if more and more information was obtained, the probability₁ must tend towards the relative frequency (probability₂).

Tintner states that Carnap’s degree of confirmation satisfies this requirement. His concluding qualification identifies where the choice of fundamental measures matters: small samples, where information remains limited. Increasing information should bring convergence toward relative frequency, but this does not render the initial assignment of measures irrelevant. Carnap’s theory, as then presented, could contribute precisely in such information-poor situations. The reply’s significance lies in this compact reconciliation of conceptual distinction, convergence, and the practical importance of inductive judgments when evidence is sparse.