The exact year is not so important.<p>With everything we know now, what would you tell the people in 100 BCE that would improve society?<p>Reason I ask is because this question frustrates me as to how little I could actually benefit the world in 100BCE. Best thing i could think of is washing your hands. So I come to the bright minds at HN to redeem myself.
By 100BCE the Greek classical period had already passed and Rome was on the rise. A high level of culture existed in places and sophisticated thought was commonly expressed in written form.<p>Metallurgy was sufficient. Many of the works of artisans and craftsmen haven't been duplicated. A great majority of this knowledge was lost to time (c.f., the fire of Alexandria) because copying texts was an enormous amount of work.<p>Also, even if a great body of knowledge were imparted to people in that period, who's to say that it would be disseminated? The knowledge that went into the construction of the Antikythira mechanism--even the knowledge that such knowledge existed--was lost.<p>So I would push up the invention of the printing press by 1.5 millenia.<p>Even without imparting any additional knowledge, the sheer volume of written material that would have been passed down through the centuries would guarantee more rapid advancement of civilization, as well as preservation of history. We would have the works of Sappho, for example. And history would still progress naturally, without artificial interference.
<i>"I am, probably was, the sandwich maker for a small tribe. It was a bit embarrassing really. When I first arrived, that is, when they rescued me from the wreckage of this super high-technology spacecraft which had crashed on their planet, they were very nice to me and I thought I should help them out a bit. You know, I'm an educated chap from a high-technology culture, I could show them a thing or two. And of course I couldn't. I haven't got the faintest idea, when it comes down to it, of how anything actually works. I don't mean like video-recorders, nobody knows how to work those. I mean just something like a pen or an artesian well or something. Not the foggiest. I couldn't help at all. One day I got glum and made myself a sandwich. That suddenly got them all excited. They'd never seen one before. It was just an idea that had never occurred to them, and I happen to quite like making sandwiches, so it all sort of developed from there.'</i><p>I'd tell them the same thing I tell people now. What you think you know, you don't know. There is more to learn than you can possibly imagine, and, most importantly, there's nothing like a good sandwich.
Boil water before you drink it. Water has evil spirits in it. They kill more people than anything else and will for the next two thousand years. Fire spirits chase the evil water spirits away -- you can tell because when they leave the water, it bubbles.
Your question made me think of this:<p><a href="http://www.qwantz.com/fanart/timetravelling.jpg" rel="nofollow">http://www.qwantz.com/fanart/timetravelling.jpg</a><p>All useful information, but you have a point about the receptivity of the world in 100BCE. If you start talking about germs spreading disease, people are going to assume you are talking about demons and are possessed.<p>I'd probably try to find some leading scientific minds of the day (Jing Fang, Marcus Pollio, or the people that created this: <a href="http://en.wikipedia.org/wiki/Antikythera_mechanism" rel="nofollow">http://en.wikipedia.org/wiki/Antikythera_mechanism</a>) and work with them to 'discover' new ideas. They would probably be eager to learn, and could take your ideas and put them in the context of the age. Of course, you'd have to learn some ancient Greek and Chinese first. ;)
I would tell them the benefits of standardization and assemblage. Making things to specification is a little appreciated, but very useful, concept.<p>E.g., a component of America's success in many wars (although I've read the disparity between her forces and the enemies were greatest during the Revolutionary War) was the fact that the gunsmiths made parts to spec. So I could buy my gun in NY and have it repaired with off the shelf parts down in Virginia.<p>For all the printing press folks, I think a big part of the success of the Gutenberg press was the fact that it was one design, could be build and distributed, and could be fixed from standard parts. Don't ever underestimate the influence of maintenance!
I know we look different, but really, we're all about the same; this is electricity; this is called a lens; this is the scientific method; keep your animals further apart; prosperity through trade, not war and looting; drink hot tea and beer; mix tallow and ash.<p>Oh, and of course:
e^ix = cos x + i sin x
Hand washing would be a difficult sell, even as late as the 19th century: <a href="http://en.wikipedia.org/wiki/Ignaz_Semmelweis" rel="nofollow">http://en.wikipedia.org/wiki/Ignaz_Semmelweis</a>
You almost certainly know whatever level of mathematics is above the one available. In the Mediterranean at this point in history, they're just circling around the idea of integration, but won't actually make it there.<p>Here's a protip: download wikipedia to your phone today. As soon as you realize that you've been trapped in the past, <i>turn it off</i>. Turning it on briefly will allow you to access stores of vital information before the battery runs out.<p>Unless this is Terminator rules, and you're naked . . .
If you could explain evolution (and get them to believe it), you'd change the course of intellectual history in some interesting ways.<p>Once you've done that, you could start on the germ theory of disease. Those are both scientific breakthroughs that you probably understand well enough to explain.
I'd make some gunpowder (charcoal, bovine poo and a couple of other easily found ingredients) and become a self-proclaimed god (with special effects and stuff). Then I'd teach my minions Klingon and we'd all be using a single language (with less than 6k words) today.
"In about a hundred years, there'll be a kid named Jesus born in Nazareth. Listen to him, he really knows his stuff. Do what he says, and you'll have the greatest society in history.
I would teatch them to learn from different cultures, I think it was a waste of time destroy everything they found in each civilization they conquered like Incas, Mayans and other civilizations in europe. Probably there were a lot a writing documents that would be very useful to our society today.
I would teach them about quicksort and mergesort.<p>Little known fact: most of the technological stagnation of the dark ages was time wasted in bubblesort.