We draw on pages 7 through 19 in Morin's Book 22 to expand upon our understanding of Significators and Promittors.

While an understanding of Primary Directions does not depend on the mathematical ability to compute them, the content of the aforesaid pages as well as a conceptual understanding of Primary Directions based on simple geometric concepts requires that we introduce several technical expressions and concepts.

They include

1. Diurnal motion of the celestial sphere,
2. A definition of the end points of an Arc of Direction/Event that are called Termini,
3. Preceding and Following Termini and how their relationship to one another is based on the direction of motion of the diurnal motion of the celestial sphere, and
4. The reduction of the zodiacal longitude of termini to their corresponding right ascension.