A journey is only one visible episode within a much denser temporal system of routines, relocations, residences, family relations, work, education, transport competence and repeated exposure to distance. The decisive shift is from counting movement as event to reading movement as trajectory. Scheiner’s mobility biography supplies this shift by showing that travel behaviour acquires temporal depth through path dependence: stable habits persist, key transitions interrupt them, and different partial biographies—residential, household, educational, professional—continually modify one another. A forty- or fifty-year mobility record is therefore not a linear itinerary. It is a stratified system in which periods of intense international circulation coexist with years dominated by commuting, family travel, local cycling, repeated returns or one stable base generating hundreds of radial movements. Long duration also changes what counts as evidence. Memory can recover major relocations, family journeys, schools, workplaces, accidents, relationships and recurrent destinations more reliably than precise frequencies or exact distances decades later. The life course calendar formalises this asymmetry instead of concealing it: years become temporal containers in which several domains can be aligned, compared and corrected.
