Monday
Monday demonstrates absolute temporal precision. It arrives every seven days without exception, deviation, or negotiation. This predictability has persisted since the adoption of the seven-day week in ancient Babylon, representing approximately 4,000 years of unbroken reliability. One may set calendars, schedules, and indeed entire civilisations by Monday's arrival. The Gregorian calendar reform of 1582 adjusted dates but preserved Monday's weekly return. Even time zone variations merely shift the hour of Monday's arrival, never preventing it. This clockwork inevitability contributes significantly to Monday's psychological impact—the knowledge that it will come, regardless of prayers, bargaining, or existential rebellion. Scientists have noted that Monday is, in fact, more predictable than sunrise, which varies by location and season, whilst Monday remains constant in its seven-day cycle across all latitudes.
Glacier
Glaciers present a complex predictability challenge for modern science. Their behaviour depends upon numerous variables: temperature, precipitation, topography, and increasingly, anthropogenic climate change. Whilst their general direction of flow can be predicted, specific movements prove frustratingly variable. The Jakobshavn Glacier in Greenland, for instance, has alternated between advancing and retreating multiple times this century alone. Glaciologists employ sophisticated models incorporating ice dynamics, basal hydrology, and atmospheric forcing, yet predictions remain uncertain beyond decadal timescales. Calving events—when icebergs break away—occur with particular unpredictability, making glacier observation a perpetually surprising endeavour. This unpredictability, whilst scientifically fascinating, undermines the glacier's reliability as a cosmic constant compared to Monday's unwavering temporal fidelity.