Yuga

Yuga is a term in Hindu cosmology for an age or era within the larger cycle known as a mahayuga or simply a cycle of four ages. The word yuga comes from Sanskrit and means “age” or “period.” Time is described as cyclical, with four yugas following one another in a fixed order.

The four yugas in a mahayuga are Satya (Krita) Yuga, Treta Yuga, Dvapara Yuga, and Kali Yuga. Their traditional lengths are: Satya Yuga 1,728,000 years; Treta Yuga 1,296,000 years; Dvapara Yuga 864,000 years; Kali Yuga 432,000 years. The sum is 4,320,000 years for a complete cycle, after which the cycle begins again.

Moral and spiritual conditions define each yuga: Satya Yuga is described as the age of truth and virtue; Treta and Dvapara Yugas see a gradual decline; Kali Yuga is characterized by strife, ignorance, and loss of dharma. The varying lengths and qualities are used to explain changes in human behavior and society across cosmic time.

In many traditions, the present age is Kali Yuga, which began around 3102 BCE with the death of Krishna. It is prophesied to end with the appearance of Kalki, the future avatar of Vishnu, after which a new Satya Yuga begins. The yugas are used in Hindu calendars and cosmology to frame ethical and historical narratives.

The concept also appears in other Indian religious texts with variations, but the Hindu framework remains the most elaborated and influential.