They recognized the importance of the heliacally rising constellation as markers for the astrological ages and claimed that knowledge of this phenomenon had been known for thousands of years previously.
They claim that to understand ancient thinking it is necessary to understand astrology, not the modern sun-sign or horoscopic astrology, but the astrology of ancient times which was the lingua franca of ancient times.
Referring back to the precession of the Equinoxes, as the Sun crosses one constellation in the Northern Hemisphere's spring Equinox (March 21), it will cross the opposite sign in the spring Equinox in the Southern Hemisphere (September 21).
For instance, the Age of Pisces is complemented by its opposite astrological sign of Virgo (the Virgin); so a few refer to the Piscean age as the 'Age of Pisces-Virgo'.
Paul Wright in The Great Ages and Other Astrological Cycles believes that much of the uncertainty related to the astrological ages is because many astrologers have a poor understanding of the meaning of the astrological symbolism and "even poorer historical knowledge".
Though so many issues are contentious or disputed, there are two aspects of the astrological ages that have virtually unanimous consensus—firstly, the claimed link of the astrological ages to the axial precession of the Earth and commonly referred to as precession of the equinoxes; Astrologers use many ways to divide the Great Year into twelve astrological ages. One method is to divide the Great Year into twelve astrological ages of approximately equal lengths of around 2160 years per age based on the vernal equinox moving through the sidereal zodiac.
What is highly contentious in modern times is the claim by many that observation of the effects of precession of the equinoxes was known well before the time of Hipparchus and his contemporaries in Greece or even Mesopotamia.
The academic answer is no – precession of the equinoxes was unknown in earlier times.
Some astrologers believe that during a given age, some events are directly caused or indirectly influenced by the astrological sign associated with that age, while other astrologers believe the different astrological ages do not influence events in any way.
Many astrologers consider the entrance into a new astrological age a gradual transition called a "cusp".
For example, Ray Grasse states that an astrological age does not begin at an exact day or year.
Santillana and von Dechend believed that the old mythological stories handed down from antiquity were not random fictitious tales but were accurate depictions of celestial cosmology clothed in tales to aid their oral transmission.
The chaos, monsters, and violence in ancient myths are representative of the forces that shape each age.