Kepa Ruiz-Mirazo is a physicist who has devoted his research career mostly to study the epistemological foundations of biology, focusing on the problem of origins of life and its non-trivial chemical roots. After completing a PhD in Sciences (Complex Systems) at the UPV/EHU, he worked as a postdoc at the Centre for Astrobiology (Spain), Institute for Polymers at ETH-Zürich (Switzerland), and the University Roma Tre (Italy). His main scientific contributions have been in elaborating protocell models, both in vitro and in silico. This has reinforced a theoretical perspective according to which phase heterogeneity, molecular diversity, and the functional coupling among various kinds of physical and chemical processes are essential to understand the emergence and nature of biological phenomena. Former Ramon y Cajal Fellow, KRM is PI of the IAS-Research Group (http://www.ias-research.net/), supported by Basque Government and Spanish Ministry grants, and also involved in a European ITN (https://protomet-etn.eu/).