The traditions of complexity theories

From a Science & Technology Studies (STS) point of view, the questions to be addressed to complexity theories are many, challenging and interesting ones. Before being able to approach them, though, one has to establish a perimeter of actors. Researchers and institutions aligning themselves with the concept of complexity are many and multiform around the world. Following a certain number of criteria – sources of inspiration, common ambitions and concepts, gathering institutions – I have found four traditions, two in natural sciences and mathematics, and two in social sciences. In my keynote I will motivate the choice of these criteria and will present the four traditions. I will conclude mentioning some of the questions I am addressing in the following chapters of my doctoral thesis.