Things that defy explanation: reading about rationing various countries experienced in WWII, and finding yourself in tears for a moment.

The diary of Tanya Savicheva, a girl of 11, her notes about starvation and deaths of her sister, then grandmother, then brother, then uncle, then another uncle, then mother. The last three notes say "Savichevs died", "Everyone died" and "Only Tanya is left." She died of progressive dystrophy shortly after the siege.