Natural resources management deals with highly complex socioecological systems. This complexity raises a conundrum, since wide-ranging knowledge from different sources and types is needed, but at the same time none of these types of knowledge is able by itself to provide the basis for a viable productive system, and mismatches between the two of them are common. Therefore, a growing body of literature has examined the integration of different types of knowledge in fisheries management. In this paper, we aim to contribute to this ongoing debate by integrating the evolutionary theory of innovation—and specifically the concept of proximity—and the theory of perception. We set up a theoretical framework that is able to explain not only why the different types of knowledge differ, but also why they should differ and why this divergence is useful to develop fisheries management. This framework is illustrated through a well-known complex scenario, as was the implementation of the Landing Obligation (LO) in Europe. We conclude that diversity (distance) between types of knowledge is essential for interactive learning, innovation, the incorporation of new ideas or to avoid lock-in, etc. At the same time, cognitive, institutional, geographical, etc. proximity is needed for effective communication, participation and dialogue.