Abstract: Darwinian evolutionary naturalism (DEN) is the strongest force for the legitimate expression of research in the sciences or the humanities today. I attempt to address some issues that DEN still need take under consideration. This paper is divided into three parts. Part 1 is a struggle to find a coherent definition of DEN as it is currently understood. The common thread I find running through all definitions is the following: DEN is a belief or research paradigm that excludes any teleological, theological or supernatural explanations for the elucidation of phenomena in the universe. In Part 2, I address the supposed unscientific presuppositions of DEN. This leads us to the question of scientific methodology. Famous philosopher of science Karl Popper wrote, “the criterion of the scientific status of a theory is its falsifiability, or refutability, or testability.” If we cannot or are not allowed to consider the falsifiability, or refutability of DEN, then it is according to Popper, a non-scientific theory. Is this critique true? Is DEN a non-scientific theory? Finally in Part 3, I frame and articulate to the DEN’s community a strong argument against DEN ala Alvin Plantinga and Richard Taylor. This argument states that if our cognitive faculties have arisen by purely natural, unguided forces, then, although they can be trusted to arrive at pragmatic conclusions, they cannot be trusted to arrive at truthful conclusions.