Why do sci-fi writers do this?

[Korten12]

Shit, Halo's got two.

....certain Halo just had the Forerunners. Just the one.

They recently introduced another one that achieved a higher level of technology than the Forerunners and these guys are called the Precursors. Google Precursors Halo and have a look yourself.

Actually they have been in the halo lore since the start.

In Halo: The Fall of Reach, Dr. Catherine Halsey states the the Forerunner crystal found on Sigma Octanus IV was created by a "precursor race".

From the Halo wiki.

 

[Jedoro]

It's more likely that we'll still be racially diverse and speaking English in a few hundred years, than it is in a few thousand. In all that time, we'd be able to have completely blended to where race was pretty much undefinable, and we could have some crazy superior language that makes so much more sense than English. So, the closer their timeline is to ours, the more likely things will generally be the same.

Someone has been watching South Park...

I actually didn't think about that episode until you mentioned it, but it does make sense that as we grow more tolerant of other races over time, that we'd all eventually blend into one. The language thing came from my Arabic class, in which I found out that learning another language shows you how stupid some things about English are.

 

[Owen Robertson]

Shit, Halo's got two.

....certain Halo just had the Forerunners. Just the one.

The Precursors. From that new-ish book. The intergalactic crab-people.

 

[Owen Robertson]

Even easier than introducing lost races, what about a Chaotic Neutral race, that randomly drops off a bomb and a ship. Some people escape and the rest die! That's impartial and chaotic!

 

[remnant_phoenix]

Well there are examples of this within our own history, I mean greek mathematics and philosiphy and Egyptian engineering, craft working, and farming techniques were all lost to Europe for hundreds of years only for them to rediscover them later after the crusades (the knowledge was preserved by Arab peoples during Europe's "Dark Ages") So it's not unheard of for people to find
"lost civilizations" with untold knowledge

This is a good point.

I'm not sure if it's true or not, but I heard from someone who knows a lot about history that the Great Library of Alexandria had a workable blueprint of the internal combustion engine...around the time of the birth of Christ.

Yeah, the same engine that wouldn't come into wide use until the Industrial Revolution over a millennium and a half later.

If this is true, it's a perfect example of of what agentorange98 is talking about.