In the post-truth condition, epistemic uncertainty is a key problem. If nothing can be perceived as real, true or certain, what does that mean for our ability to master our lifeworld? Human’s internalised relation to the existence/non-existence of a stable truth or recognisable reality inevitably influences how we deal with mediated reality as well as historical reality, and how we work to make sense of our past and present. What does this mean for understanding media, for writing history, for performing social science? This is our starting point for this anthology. We demonstrate how social scientists across a broad spectrum of academic fields understand processes of reality formation. When we are discussing reality formation, we discuss reality constructions based on certain experiences, expectations, interests or political intents. We do this by showcasing new empirical studies, organised in three sections; 1) (Re)constructing On- and Offline Reality, 2) Inventing/constructing Historical Reality and 3) Making Sense of Reality when Your World is at Stake, followed by a more philosophically oriented section 4) The Philosophy of Reality Construction, where we discuss challenges to truth, reality and history science in the post-truth condition.