Abstract
This article aims to approach the problem of predictability and unpredictability and their impact on Library Research as a social discipline. For that purpose, some conceptual clarifications are proposed in regards to statements, observations, experimental laws and theoretical systems. Furthermore, an analysis is made of the links between these concepts and scientific prediction. Finally, the contributions by Kuhn, Lakatos and Kuipers regarding this issue are presented, with the purpose of finally showing that Library Research developments are framed in the knowledge generation with an unpredictable nature in principle