Kalpa (aeon)

Kalpa (Sanskrit: कल्प kalpa) is a Sanskrit word meaning an aeon, or a relatively long period of time (by human calculation) in Hindu and Buddhist cosmology. The concept is first mentioned in the Mahabharata. Romila Thapar holds that "the kalpa is first referred to in the inscriptions of Asoka". In the Pali (= early Buddhist) form the word kappa is mentioned in the assumed oldest scripture of Buddhism, the Sutta Nipata, where it speaks of "Kappâtita: one who has gone beyond time, an Arahant". This part of the Buddhist manuscripts dates back to the middle part of the last millennium BCE.

Generally speaking, a kalpa is the period of time between the creation and recreation of a world or universe. The definition of a kalpa equaling 4.32 billion years is found in the Puranas—specifically Vishnu Purana and Bhagavata Purana.

According to Visuddhimagga, there are several explanations for types of kalpas and their duration. In the first explanation, there are four types:

In another simple explanation, there are four different lengths of kalpas. A regular kalpa is approximately 16 million years long (16,798,000 years), and a small kalpa is 1000 regular kalpas, or about 16 billion years. Further, a medium kalpa is roughly 320 billion years, the equivalent of 20 small kalpas. A great kalpa is 4 medium kalpas, or around 1.28 trillion years.

Buddha had not spoken about the exact length of the maha-kalpa in number of years. However, he had given several astounding analogies to understand it.

1. Imagine a huge empty cube at the beginning of a kalpa, approximately 16 miles in each side. Once every 100 years, you insert a tiny mustard seed into the cube. According to the Buddha, the huge cube will be filled even before the kalpa ends.

2. Imagine a gigantic rocky mountain at the beginning of kalpa, approximately 16 x 16 x 16 miles (dwarfing Mount Everest). You take a small piece of silk and wipe the mountain once every 100 years. According to the Buddha, the mountain will be completely depleted even before the kalpa ends.

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