A few years ago, a man named Florian Schuhmacher toured the country’s talk shows. He sat by Beckman and hard but fair and there praised the advantages of a presumptuous life. Schuhmacher is an excessive self-tracker, so he meticulously records a lot of data about his body: How much did I move today? How was my pulse? How did I sleep? And how am I feeling mentally about all of this? He therefore belongs to the Quantified Self movement. Its members are convinced that they have found the key to a better life in constantly checking and measuring their bodies. People like Florian Schuhmacher were still rarities back then, in the 2010s.