36
$\begingroup$

John from our future, takes the time-travel bus back in time and steps off in 5th century Europe. He heads for the secret location where travellers are kitted out with authentic clothes, food and currency to keep them alive until they can establish themselves. He has learned enough of the local language to pass for a foreigner. He tells the locals he is from "Nonsylvania" or "far to the North" or such.

By time-travel law, he was not allowed to carry any artefact back with him and he didn't. He purchased a return ticket and and can use it by going back to the hideout according to the timetable. He is not allowed to make repeat journeys for any reason.

John is an entrepreneur. He left school early to work in a local market. He doesn't have scientific or detailed historical knowledge. There is no way he could invent even electric power. He doesn't know how to make rubber. If he wants to "invent" something that he knows about from his own century, he must do it with ancient tools and technology and get the locals to make it.

However John, contrary to all the rules of time-travel, wants to change the ancient world.

He settles on one simple invention from later than the 5th century that he can make and sell to build his business. He can employ local crafts people but they can only use their ancient tools.

My first thought was scissors but it turns out they were invented around 1500 BC in ancient Egypt.

Question

I then thought of a can-opener (invented around 1810) but then he would have to invent cans. Given that John knows little about metals or where to find them, is it feasible that he could make this "invention" and set up his 5th century worldwide business empire?

Can he make cans? If he can't make cans, what can he make?

Assumptions

  1. John has done no research before leaving. He is a businessman not a historian or scientist. His plan is to look around when he gets there and see if they are missing any everyday objects that he knows about. He only has to have a rough idea how to make them and maybe draw a sketch for the local blacksmith to try and emulate. He must rely on local skills, tools and knowledge to do the actual manufacturing.

  2. By tool I mean a solid object, e.g. scissors, paperweight, hammer, axe, etc. Remember that John was not allowed to take any artefacts back in time (and didn't). He has to work from memory. Hence he will probably pick something simple but very useful.


Detailed timeline of inventions from Wikipedia https://en.wikipedia.org/wiki/Timeline_of_historic_inventions


EDIT - in defence of John

NOTE - What follows, superficially looks like story-line but it is actually an explanation of the conditions I set. Without clear conditions a question like this becomes far too open-ended.

Many people have queried John's lack of knowledge and research. John does not spend all his time on Worldbuilding, so he does not know about "black powder" and other arcane subjects. He is a man-in-the-street who made good. All his expertise lies in: making money, influencing people, spotting gaps in the market, organising teams to do the things he doesn't have the expertise for, etc. He was moderately rich and successful when he lived in his own century. Thus his skills are fully formed. Now that he can afford time-travel (it's very expensive), he is setting out on the adventure of his life. Instead of being a big fish in a medium-sized pond, he wants to be a big fish in the pond that is 5th century Earth. He didn't do research before starting because he isn't that kind of guy. He enjoys landing on his feet in a new situation and thinking fast. His intention is to spot gaps in the market - at first locally and then more and more widely. He will diversify when necessary and concentrate on efficient manufacturing and distribution - out-competing others when he can, and forming partnerships with them when he can't

$\endgroup$
  • 1
    $\begingroup$ Comments are not for extended discussion; this conversation has been moved to chat. $\endgroup$ – L.Dutch - Reinstate Monica Jul 18 at 3:00
  • $\begingroup$ does invention from other regions ok ? such as paper? or maybe silk making? or this must change the ancient world as a whole? no one invented yet? does john come there naked ? or he also come with his modern clothing? or do he know concrete making? $\endgroup$ – Li Jun Jul 18 at 3:49
  • $\begingroup$ Think of the world in the first half of the 19th century (Napoleonic wars, American War of Secession). Compare it with the world in the Antiquity. Do they look the same to you? No, they don't. In the (classical, Greco-Romano-Persian) Antiquity they didn't have -- buttons, paper, steel, cotton gins, water powered looms, lathes for machining metal, tailored clothing, uniform units of measurement, telescopes, efficient sailing ships, efficient rudders for the ships, strong alcoholic beverages, mariner's compasses, firearms and cannon, horse collars, cheap glass, bottles with stoppers, &c. &c. &c. $\endgroup$ – AlexP Jul 18 at 5:32
  • 6
    $\begingroup$ Mike Scotts answer, which would actually work, brings up another problem, anything John is capable of describing how to make, other people can copy without giving him a dime. If it doesn't require technical knowledge there is nothing stopping people from copying it, patent laws were extremely rate and basically only granted by royalty, so only good for a single country. $\endgroup$ – John Jul 18 at 14:03
  • 3
    $\begingroup$ Cans would require a degree of metallurgy that was not available in ancient times. It took until the 1800s until sheet metal was available that could be pressed into cans in a cost-effective way. $\endgroup$ – papirtiger Jul 18 at 14:05

36 Answers 36

1
2
0
$\begingroup$

Saltpetre. Potassium nitrate. Explosives and firearms. Although he equally could have com from the past (and be South Asian) to 5th century Europe as the future. But gunpowder would only reach China in the 9th century, then Turkey, the Middle East, and finally Europe in the 13th century.

You asked, if it is "feasible" he could make this "invention" and "set up his 5th century worldwide business empire". This would allow him to establish a worldwide "empire" (no qualifications like "business" necessary), a good 800 years early.

And yes, with just a local blacksmith, etc. He just would have to know which rocks to use; and how not to make it NOT explode before he wanted it to, but um, that's the foundation for empire. Business comes afterward.

| improve this answer | |
$\endgroup$
  • 2
    $\begingroup$ Gunpowder does not ensure military success, especially the more primitive your firearms. Plus you would need to set up a complex logistical supply train to deal with squirreling these resources (particularly sulfur). It might be more helpful to OP if you detailed out the challenges/benefits of this scenario. $\endgroup$ – Cosmic Orrery Jul 18 at 13:40
  • 2
    $\begingroup$ Plus John does not know how to make it, he is explicitly stated to have done zero research, so he will not know what rocks to use, in what proportions, nor how to properly refine them to make something useful. making black powder is not easy. $\endgroup$ – John Jul 18 at 13:47
  • $\begingroup$ @John I disagree. "John Q. Public" generally does know how to make gunpowder without explicit prior research (every heard of "science class"?), although some of the necessary chemicals were called by different names back then. $\endgroup$ – The Daleks Jul 18 at 22:54
  • $\begingroup$ @TheDaleks I would argue most don't making gunpowder is more more than just mixing three chemicals, you have to know how to refine said chemicals and how to prepare the powder, you can get something that burns easily getting something that explodes requires knowledge. Potassium nitrate in particular is almost impossible to get if you don't know how to refine it. $\endgroup$ – John Jul 19 at 3:24
  • $\begingroup$ @TheDaleks That's a ridiculous notion. Even if you could get the raw materials (pretty hard without research!), you would have no idea what the proper ratio is - and that's the tricky thing about making gunpowder. The real world is not like Minecraft where you throw stuff on the crafting table and get gunpowder :) $\endgroup$ – Luaan Jul 19 at 14:41
0
$\begingroup$

Penicillin

There's a good chance that our hero has read about the accidental discovery of penicillin in a high school textbook. Given this, it shouldn't be hard to recreate the experiment, even with very primitive cooking utensils. You need some kind of jelly that's good for cultivating bacteria, a source of bacteria, and a little speck of mold.

You have to be lucky enough to find mold that contains the penicillium organism, and it may take a few tries before you succeed. After that, you need to learn how to cultivate penicillium and how to to purify penicillin, at least to some degree. It doesn't have to be anywhere near the standards for today's drugs.

Penicillin is a powerful weapon against many diseases caused by bacteria. Once the people have begun using penicillin against disease, they will never go back to the way they were before.

| improve this answer | |
$\endgroup$
  • $\begingroup$ Thanks for your answer. Don't forget to check other people's suggestions before posting yours.. This has already been proposed by @Aww_Geez - Others have posted their objections to the idea in the comments. $\endgroup$ – chasly - supports Monica Jul 19 at 12:46
0
$\begingroup$

None.

There is common misconception that history is linear and things get invented and change the world. It's false.

Things get invented, then they fall into obscurity and get reinvented anew. Sometimes they even get forgotten after a period of widespread success, like phalanx formation.

John needs the same thing as Beth from 2348 who traveled to today with knowledge how to beat COVID-19 in 3 simple steps: being trusted by powerful and rich people who can make it happen. The thing that an outsider, like a time traveler, can never have.

John can't change the ancient world, just like Beth can't stop what's going to happen in early 2021.

| improve this answer | |
$\endgroup$
0
$\begingroup$

Better agricultural practices

By introducing better plow technology like mouldboard plows and introducing techniques like crop rotation, you can start the agricultural revolution 1000 years earlier. This means a drastic increase in the yield of farmland, which allows to sustain a higher population density with less labor bound to food production. So you have a lot more labor available for all kinds of economic branches... or if you are more cynical, more disposable manpower to send into wars.

| improve this answer | |
$\endgroup$
  • $\begingroup$ Well, crop rotation is way older than Antiquity. It's even mentioned in Old Testament. This only proves my point: what's necessary is not the ability to make something, but the ability to convince large amount of people to do it. $\endgroup$ – Agent_L Jul 21 at 15:10
0
$\begingroup$

The Toothbrush

According to Wikipedia:

The first bristle toothbrush resembling the modern one was found in China. Used during the Tang Dynasty (619–907), it consisted of hog bristles.

So, if John introduced it to Europe a couple hundred years earlier (and got people to believe it would help them live longer and actually use it), it might change things significantly.

| improve this answer | |
$\endgroup$
0
$\begingroup$

I'm going to take the crazy approach and try for something new: polycarbonate and/or epoxy.

Just think for a second. Transparent fairly light shields that wont budge with a direct crossbow or war bow impact that could shatter an iron shield. Seafaring ships inmune to sea worms. Lightweight vehicles and structures that needs less horse power to move the same cargo. The sky is the limit!

| improve this answer | |
$\endgroup$
  • $\begingroup$ These require petrochemicals and all the associated refining technology, which in turn requires all the associated metalworking and metallurgy and and knowledge of chemistry. $\endgroup$ – DKNguyen Jul 21 at 1:18
1
2

Not the answer you're looking for? Browse other questions tagged or ask your own question.