Philosophy, Science

Karl Popper and Rudolf Carnap Revisited

In his classic book Significance and Basic Postulates of Economic Theory (1938) Terence W. Hutchison  makes the case for economics as an empirical science.

An interesting aspect about this book is the ease with which Terence W. Hutchison uses logical empiricist authors like Moritz Schlick, Rudulf Carnap, and Otto Neurath but also the “critical rationalist” Karl Popper in making his case for the testability of economic theories.

On a number of occasions Rudolf Carnap himself has drawn attention to Popper’s habit of exaggerating the differences between his work and the logical empiricists. Historians of philosophy, or at least those with little training in the philosophy of science, have often followed Popper in his views while ignoring the quite substantial agreements between the logical positivists and Popper on topics such as the unity of scientific method and their common objective to find criteria to distinguish science from other activities.

In hindsight, Popper’s compulsive need to distance himself from the logical positivists has harmed his own project more than he could have anticipated. The traditions of thinking and social inquiry that Popper railed against, and hoped to defeat by his non-justificationist philosophy and falsification criterion, were often identified as problematic by the logical positivists as well. It is rare to find a philosopher or social scientist dealing in obscurantism and anti-empiricism who rejects logical positivism but praises Karl Popper’s demarcation between science and non-science and his views on falsifiability.

But until the dominant reception of logical empiricism as a monolithic enterprise with little more to offer than its verification principle persists it is doubtful that the broader concerns of Rudolf Carnap and Karl Popper will receive the attention they deserve. A promising start would be for philosophers to seriously engage with the work of Carnap instead of judging it on the basis of Karl Popper’s views. For example, in his later writings Carnap recognized both the problems with the classic verification principle and Popper’s falsification  principle and proposed a more liberal criterion of confirmability. As Carnap would be the first to recognize, this proposal may turn out to be either too liberal or too restrictive after detailed analysis, and further refinement may be necessary. Last, but not least, Carnap is also an admirable example of how one can do philosophy of science without (political) hyperbole.