user2235: Wikipedia's Kalpa(aeon) in Buddhism article says,

In another simple explanation, there are four different lengths of kalpas. A regular kalpa is approximately 16 million years long (16,798,000 years[1]), 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.

I just went through the Visuddhimagga, and could not find where or how that time in years is calculated.
I was wondering how to calculate it.
Please explain how it's calculated, with reference to scripture where Lord Buddha mentioned it, and/or where the calculation or the result of the calculation is described, perhaps in the Thripitaka or Visuddhimagga?

[1] Wikipedia's reference is to a book:

Epstein, Ronald B.(2002). Buddhist Text Translation Society's Buddhism A to Z p. 204. Buddhist Text Translation Society. ISBN 0-88139-353-3, ISBN 978-0-88139-353-8.

Perhaps that book may have a reference to where they found it, but I still haven't find that book.

user8044: It is not possible for anyone to have any idea of what an aeon (world cycle / kappa) is. It is equivalent to eternity. Only by a simile you will get an idea of it. The Buddha offers two vivid similes to suggest the eon's duration.
A maha kappa or aeon is generally taken to mean a world cycle. How long is a world cycle? In Samyutta ii, Chapter XV, the Buddha used the parables of the hill and mustard-seed for comparison:
Suppose there was a solid mass, of rock or hill, one yojana (eight miles) wide, one yojana across and one yojana high and every hundred years, a man was to stroke it once with a piece of silk. That mass of rock would be worn away and ended sooner than would an aeon.
Suppose there was a city of iron walls, one yojana in length, one yojana in width, one yojana high and filled with mustard-seeds to the brim. There-from a man was to take out every hundred
years a mustard-seed. That great pile of mustard-seed would be emptied and ended sooner than would an aeon.

user811: As far as I know, the words used in Buddhist Kalpa in a lot of cases, 
for example: Existence, life reduced (when life human destiny decreased from 84,000 years to 10 years),increased lifetime (as opposed to lifetime reduction),
Sub-Kalpa (approximately 16 million years),
Mid-Kalpa (20 sub-life),
Big-Kalpa (4 centered life = 1.3 billion years),
and countless Kalpa ..etc

2235: <p>Wikipedia's <a href="http://en.wikipedia.org/wiki/Kalpa_%28aeon%29#Buddhism" rel="nofollow">Kalpa(aeon) in Buddhism</a> article says,</p>

<blockquote>
  <p>In another simple explanation, there are four different lengths of kalpas. A regular kalpa is approximately 16 million years long (16,798,000 years<sup><code>[1]</code></sup>), 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.</p>
</blockquote>

<p>I just went through the Visuddhimagga, and could not find where or how that time in years is calculated.</p>

<p>I was wondering how to calculate it.
Please explain how it's calculated, with reference to scripture where Lord Buddha mentioned it, and/or where the calculation or the result of the calculation is described, perhaps in the Thripitaka or Visuddhimagga?</p>

<hr>

<p><sup><code>[1]</code></sup> Wikipedia's reference is to a book:</p>

<blockquote>
  <p>Epstein, Ronald B.(2002). Buddhist Text Translation Society's Buddhism A to Z p. 204. Buddhist Text Translation Society. ISBN 0-88139-353-3, ISBN 978-0-88139-353-8.</p>
</blockquote>

<p>Perhaps that book may have a reference to where they found it, but I still haven't find that book.</p>
 8044: <p>It is not possible for anyone to have any idea of what an aeon (world cycle / kappa) is. It is equivalent to eternity. Only by a simile you will get an idea of it. The Buddha offers two vivid similes to suggest the eon's duration.</p>

<p>A maha kappa or aeon is generally taken to mean a world cycle. How long is a world cycle? In Samyutta ii, Chapter XV, the Buddha used the parables of the hill and mustard-seed for comparison:</p>

<p>Suppose there was a solid mass, of rock or hill, one yojana (eight miles) wide, one yojana across and one yojana high and every hundred years, a man was to stroke it once with a piece of silk. That mass of rock would be worn away and ended sooner than would an aeon.</p>

<p>Suppose there was a city of iron walls, one yojana in length, one yojana in width, one yojana high and filled with mustard-seeds to the brim. There-from a man was to take out every hundred
years a mustard-seed. That great pile of mustard-seed would be emptied and ended sooner than would an aeon.</p>
 811: <p>As far as I know, the words used in Buddhist Kalpa in a lot of cases, </p>

<p>for example: Existence, life reduced (when life human destiny decreased from 84,000 years to 10 years),increased lifetime (as opposed to lifetime reduction),</p>

<p>Sub-Kalpa (approximately 16 million years),</p>

<p>Mid-Kalpa (20 sub-life),</p>

<p>Big-Kalpa (4 centered life = 1.3 billion years),</p>

<p>and countless Kalpa ..etc</p>
