Chronobiology is the science of biological time, of our daily rhythms – we call them circadian rhythms* – and the seasonal rhythms that govern our behaviour and physiology. In the course of evolution, the changing pattern of day and night across the seasons has been a powerful signal. All living organisms have internalised these external, geophysical rhythms as a biological clock. From the smallest bacteria, fungi and plants to flies and fish and mammals, living things all have a remarkably similar set of ‘clock genes’ that generate an internal cycle of about twenty-four hours.
ANNA WIRZ-JUSTICE, NEUROBIOLOGIST
Anna Wirz-Justice, ‘Daylight’, in Olafur Eliasson: In Real Life, London, 2019, p. 42.

all knowledge is recursive, inasmuch as it always involves calibrating the means of knowledge (empirical and analytical procedures, experimental protocols and tools, scales of measurement, assumptions, concepts — in short, its ‘equipment’) with the object of knowledge [...] to know something is recursively to adjust one’s body of knowledge to it.

Recursivity differs from reflexivity. Reflexivity refers to reflection on one’s own position, and in our research contexts could indicate anthropologists coming to new understandings of themselves through reflecting on others, or other people thinking about anthropologists and thus coming to altered understanding of themselves.
Recursivity, however, is about a ‘sequence of revelation’ in which the relation between two perspectives ‘is constantly redefining the partners in the exchange, the objects of exchange, and the very concept of exchange’ (Sansi 2018: 123). As such, recursivity is performative and implies action. It refers to an ongoing mutually affecting relationality between things, people, thoughts and forms of knowledge. This is not just a combination of reflexive processes but the generation of something new. More than just anthropologists and curators thinking about each other, recursivity can — perhaps in a long series of additive moves — lead to altogether novel positions. In the context of laboratory stem cell research, Sarah Franklin (2013: 20) points to what is necessary to achieve this: Recursion, in this sense — attention to the properties of the equipment you are using to determine, or manage, the properties of something else — is itself an empirical, necessary and pragmatic art