How long has civilisation been going?

I didn’t realise how short human history was.  Somewhere around 130,000 years ago we were standing upright as we are today.  Somewhere around 50,000 years ago we broadly arrived at:

the fully modern capacity for Culture *

That’s roughly when we started, “routine use of bone, ivory, and shell to produce formal (standardized) artifacts”.  Agriculture and humans staying still to grow plants happened at about 10,000BCE (or 12,000 years ago).

Writing started happening around 6600BCE* (8600 or so years ago).

This year is 5777 in the Hebrew calendar.  So someone has been counting for roughly that long.

The pyramids are estimated to have been built at around 2600 BCE (4600 years ago)

Somewhere between then and zero by the christian calendar we sorted out a lot of metals and how to use them.

And somewhere between then and now we finished up all the technological advances that lead to present day.


But it’s hard to get a feel for that.  Those are just some numbers of years.  Instead I want to relate that to our lives.  And our generations.

12,000 years ago is a good enough point to start paying attention to.

If a human generation is normally between 12* and 35* years.  Considering that further back the generations would have been closer to 12 years apart and today they are shifting to being more like 30 years apart (and up to 35 years apart).  That means the bounds are:

12,000/12=1,000
12,000/35 = 342

342-1000 generations.  That’s all we have.  In all of humanity.  We are SO YOUNG!

(if you take the 8600 year number as a starting point you get a range of 717-242.)


Let’s make it personal

I know my grandparents which means I am a not-negligible chance to also know my grandchildren and maybe even more (depending on medical technology).  I already have a living niece so I have already experienced 4 generations.  Without being unreasonable I can expect to see 5 and dream to see 6, 7 or infinite.

(5/1000)->(7/342) = between a half a percent and two percent of human history.  I will have lived through 1/2% – 2% of human generations (ignoring longevity escape for a moment) to date.

Compared to other life numbers:

Days in a year * 100 year = 36,500 days in a 100 year lifespan.

52 weeks *100 = 5200.  Or one week of a 100 year lifespan is equivalent to one generation of humans.

12,000 years / 365 days = 32.8 years.  Or when you are 32 years old you have lived more days than humans have been collecting artefacts of worth.

8600 years/365 = 23.5 years.  Or when you are 24 years old you have lived one day for every year humans have had written records.


Discrete human lives

If you put an olden day discrete human life at 25 years – maybe more, and a modern day discrete life at 90 years and compare those to the numbers above

12,000/25 = 480 discrete human lifetimes

12,000/90=133 discrete human lifetimes

8600/25=344 discrete human lifetimes

8600/90=95 discrete human lifetimes

That’s to say the entire of recorded history is only about 350 independent human lives stacked end on end.

Everything we know in history has been done on somewhere less than 480 discrete lifetime runthroughs.


Humanity is so young.  And we forget so easily that 500 lifetimes ago we were nothing.


Meta:  Thanks billy for hanging out and thinking about the numbers with me.  This idea came up on a whim and took a day of thinking about and about an hour to write up

Cross posted to lesswrong: http://lesswrong.com/lw/p9r

This entry was posted in models of thinking and tagged , , , , , , , . Bookmark the permalink.

One Response to How long has civilisation been going?

  1. Pingback: Rational Feed – deluks917

Leave a Reply