Abstract: Butler’s Introduction to Library Science is an important piece of work in the history of library
science. Reinterpreting this work will provide an in-depth understanding of Butler’s librarianship philosophy
and methods and deepen the research of today’s library science. Starting with the text interpretation, the
paper digs deep into the logic of argumentation behind it. With his grand research vision, Butler established
and demarcated the use of scientific methods in library science, and clarified the areas where scientific
methods and humanistic methods should be adopted respectively.

Key words: Butler, The essence of science, The methodology of librarianship