Against the backdrop of an administration-led renaming of the former disciplinary "Library, Information and Archive Management" into "Information Resource Management" in China and the resulting pressure for Library Science to innovate itself within the new disciplinary structure, this paper discusses what makes the disciplinary core of Library Science and how the discipline should innovate itself while retaining its core. It does so by a revisit to the concept of the library first. It shows that the essential feature of a library is its function to enable information search and access. While it is common for libraries to exist as institutions, as places and as collections of literature, it is universal for all libraries to exist as a functional entity to ensure information discoverability and accessibility. Therefore, the disciplinary core of Library Science and its extended version Library and Information Science is its concern with human beings' fundamental needs to search and access information. This also provides the discipline a sense of direction for its innovations.