Public administration suffers from the problem of the logical division between facts and values if modernity is seen as the thoughts of logical positivism and instrumental rationalism. The instrumental rationality of modernity presented the concepts of efficiency, effectiveness, expertise, professionalism, accountability, and democracy and other issues in PA. On the other hand, interpretivism is based on the belief that there is no objective reality out there and reality is socially constructed. Reality is not something that exists outside the researcher as is the case under the positivist perspective. This article discusses how the two different theories, positivism and interpretivism, influence the way of thinking and practicing in the field of public administration.