History of science assumes that ‘the new’ does not come into the world unprecedented. One of the fields in which the apparent conflict between models of more or less complexity have in the past two centuries been discussed in biology with most rigor much before the advent of systems biology and later became one of its major fields of application was inheritance (later genetics and development/embryology and finally epigenetics).

This paper’s point of departure is an analysis of models at the moment of the change from heredity to inheritance and genetics. It explores the relationship and potential parallels in the conflict of less complex, more static, mechanicist (bottom-up) models and non-mechanicist (top down) models in biology in the late 19th and early 20th century with the situation today. It does so along the example of inheritance, asking for the respective reasons and moral economy in the use of either concept.

The fundament for a mechanistic view on hereditary processes in organisms was introduced mainly by researchers in the German Empire in the 1870s to 1890s. Just as suggested by the organizers of this panel, here indeed ‘place’ or locality does play a role: the strongly reductionist account that separated material and function of the cell plasma and the nucleus from each other took shape on the background of prevailing idealism on site and a very specific historic situation in the German lands, which was the foundation of the Empire. This reductionism found its most serious opposition not only within its country but in the research by embryologists in the US, such as the early Thomas Hunt Morgan. However, as is well known in history of science, in the 1910s Morgan adopted a nucleocentric view on inheritance with the focus on chromosomal heredity, earning himself the reproach of being reductionist.

While discussing these changes between the 1870s and 1910s in comparison to current conflicts between reductionism, non-systems and systems accounts, the historical comparison shows that in the analysis of historical and today’s models in biology it is not only useful but necessary to differentiate between different categories of reductionist or complex concepts: whether they are epistemological, methodological and ontological in many cases not only explains but solves the conflict.