What is the importance of a writing system to a civilization according to Guns, Germs, and Steel?

Writing
systems are vital to the development of civilization. Most cultures only began to truly develop
and adapt once they achieved some form of writing. This is because transcription and record
keeping have extremely important roles in human history. Writing acts to preserve the past and
tell the stories of history so that we can learn lessons and grow. But more importantly, it
allows us to record important information.

The first forms of writing were
used to give instructions on building structures and cities, to create calendars so that humans
had a better understanding of weather and harvests, and to instate laws and decrees for
civilization. Without a written document, many of these things would have failed to be achieved,
leaving civilization without much to build upon.