The method of Ludwig Boltzmann (1844 – 1906), a great Austrian physicist-philosopher, for solving philosophical problems was described. This brilliant method can be a guiding stray in philosophy. His method is not restricted to philosophy of science (scientific philosophy), and indeed it can be used as well in pure philosophy. Theoretical pluralism developed by Boltzmann can be used as a basic assumption in philosophizing the epistemological problems. The Boltzmann’s method also saves philosophy from dogmatism. It shows the usefulness of philosophy as well as progress of science, and calls for collaboration of philosophy and science. This collaboration can lead the human to better understanding of the Nature. Boltzmann states how both science and philosophy can go astray in the absence of this collaboration, since they are indeed unit.