Word origin · etymology
Historical descriptive method name.
Direction means directing or carrying a chart factor forward; primary distinguishes the method based on the sky's daily rotation.
How we know · epistemology
Historical geometric timing method
The method combines spherical geometry with a chosen conversion from arc to years. Matching the geometry tests the construction; the timing key and event interpretation remain distinct assumptions.
Connected concepts
Mentioned in 2 other entries
These links connect subjects and terminology. They do not establish a shared historical origin.
Sources & provenance
Use the citations beside each section to distinguish a calculation convention, a historical teaching and an editorial example.