Philosophers of science often ask a key question: What does it mean when we say that someone has rightly claimed that a proposed theoretical hypothesis is a true explanation of a certain phenomenon in the world? The decline of the justificatory power of perceptual observation has triggered a bifurcation in the study of the nature of justification in science―namely, the logical (or empirical) school and the practical (or social) school. This duality calls for a mediatory account, one that would provide a compromise explanation that accommodates the concerns of these two seemingly contradictory schools. Neurath's idea of scientific justification qualifies as a mediatory account, but it is incomplete, in that it is ineffective in explaining two problems: the problem of entitlement requirement and the problem of the initial learning of norms. McDowell's ideas about conceptual capacities and Bildung, and Brandom's inferentialist approach of conceptual content, which are developed under the ontological presumption that reason and nature are on the same earthly plane, seem to be helpful in bridging the chasm, or even in eliminating it, thereby making Neurath's account complete. This paper represents an attempt to apply Neurath's, McDowell's, and Brandom's ideas to resolve this key problem in the philosophy of science.