Adolf Meyer-Abich (1893–1971; known as Adolf Meyer before 1938) spent his career as one of the most vigorous and varied advocates in the biological sciences. Primarily a philosophical proponent of holistic thought in biology, he also sought through collaboration with empirically oriented colleagues in biology, medicine, and even physics (including C. J. van der Klaauw, Karl K¨otschau, Hans B¨oker, Jakob von Uexk¨ull, and Pascual Jordan) to develop arguments against mechanistic and reductionistic positions in the life sciences, and to integrate them into a newly disciplinary theoretical biology. He participated in major publishing efforts including the founding of Acta Biotheoretica. He also sought international contacts and worked for long stretches in Chile, the Dominican Republic, El Salvador, and the United States. His career straddled the Nazi period, which led him into a complex dance of support for and resistance to the regime. Despite the relative failure of his conceptual innovations (e.g., “holobiosis” and “holistic simplification”) to catch on, his ideas and writings sit squarely within the trajectory of thought and argument that has led to today’s reinvigoration of thought about conceptual integration in evolutionary developmental biology.