1 The Non-trivial Problem of Cross-disciplinary Science and

Cross-disciplinary use of science is needed to solve complex, real-world problems, but carrying out scientific research with multiple very different disciplines is in itself a non-trivial problem. Perspectives matter. In this paper we carry out a philosophical analysis of the perspectival nature of science, focusing on the synchronic structure of scientific perspectives across disciplines and not on the diachronic, historical structure of shifting perspectives within single disciplines that has been widely discussed since Kuhn and Feyerabend. We show what kinds of cross-disciplinary disagreement to expect due to the perspectival structure of science, suggest how to handle different scientific perspectives in cross-disciplinary work through perspectives of a second order, and discuss some fundamental epistemic differences between different types of science. 2 Perspective is one of the component parts of reality. Far from being a disturbance of its fabric, it is its organizing element.... Every life is a point of view directed upon the universe. Strictly speaking, what one life sees no other can.... Reality happens to be, like a landscape, possessed of an infinite number of perspectives, all equally veracious and authentic. The sole false perspective is that which claims to be the only one there is