The Yugas: Keys to Understanding Our Hidden Past, Emerging Present and Future Enlightenment by Joseph Selbie and Steinmetz is a wonderful introduction to the East Indian concept of "Yugas Cycles" or great ages that correspond to the Western idea of the Precession of the Ages in which we are now going from the Age of Pisces to the Age of Aquarius.
Just as this shift happens every 2,000 years or so and the whole precession takes 24,000 years with 12 ages in each of the zodiac signs, the Yugas Cycle takes 24,000 as it goes through the Golden Age, Silver Age, Bronze Age, and Iron Age and back again -- like a giant clock.
We are now at the bottom of the "clock", the Iron Age or Dark Age known as Kali Yuga from which we began to emerge in the 1700s as we began to enter the ascending Bronze Age (Dwapara Yuga).
The last Satya Yuga (Golden Age) began in 11,500 B.C. Consciousness descended through the declining Treta Yuga (Silver Age), and Dwapara Yuga (Energy Age), reaching its lowest level in descending Kali Yuga (Dark Age or Iron Age). We are now on the ascending side of the cycle during which consciousness is slowly rising through the ascending Energy Age and ascending Silver Age, to the ascending Golden Age.
The whole cycle or "Mayayuga" (Great Year) is 4,230,000 years or 4.23 billion years. Since the cycles have the mathematical relationship shown in "The four yugas" chart below, they form a Fibonacci Spiral -- one of the key form of Sacred Geometry on which all life and the universe is designed.
The Chart of the Yugas (shown below) which lists historical events from 11,500 B.C. until 1700 A.D. can be purchased for $7. On the back, the characteristics of each age are explained: Satya Yuga is the spiritual age, Treta Yuga is the mental age, Dwapara Yuga is the age of energy that the earth is now entering, and the Kali Yuga the dark age of material consciousness we are struggling to leave behind.
Click the graphic below to watch a video with co-author David Steinmetz explaining the Yugas.
See The Yugas for more information.
In the videos below, co-author Joseph Selbie discusses more about the Yugas. Interestingly, it seems that only the West went into major decline through the descending side of the Yugas Cycle. The East and indigenous cultures maintained much of the wisdom of higher ages.