Capitalism is only 400 years old

It's over 2000 years old. Jesus threw bankers out of the temple.

Yeah - the basis of capitalism is giving someone a loan since you believe they will pay you back more.

And that started way earlier than 400 years

I wonder where that number came from
- Before it was merely people using money.
  
  I've seen an interesting video about it a few months ago: 400 years ago is actually mercantilism. It means people build their fortune out of selling goods. Before that, it was about possessing lands and taxing the people who lived there.
  
  Capitalism is different than both. It's not born 400 years ago with the trading with the America. It's born with the industrial revolution when the bourgeoisie seized the power with democracy.
- From the Dutch who would sell shares of the profit they were going to make before a voyage. Very different from the norm at the time when usually a monarch or noble would fund such projects. I personally think it's a very good spot in history to think of the beginning of capitalism
- I think the basis for capitalism is actually that the price of a product or labor is set by the market. It probably "started" the first time Gork traded Thmm a spear for 3 shiny rocks.

Feudalism is a more simpler and unfree version of capitalism and it has existed for a very long time.

Still only a blip in human existence though.
- We're crashing head first into a new more modern version of feudalism, so while still a blip it's an ongoing blip.

What was the common system before that? Feudalism?

Mainly mercantilism which just means that everyone wants to only export and importing stuff is literally the worst thing in the world. Mercantilism also had a lot more state restrictions on it compared to capitalism.

Feudalism mainly died out in the 1400's when more of the power was centralised to the king instead of their vassals.
Feudalism, Anarchism, primitive forms of communes, etc. The world was a mixed place.

Capitalisms only became successful thanks to the ability to easily connect places. And even then it wasn't as globally dominating as it was today before we had a revolution in transport methods.

Well, communism is an unborn baby then.

Didn't people live in small communities and share stuff for quite some time during the early human times?

My knowledge on history isn't the greatest especially early stuff so Idk. But that's how I'd always imagined things before feudalism and money.
- Isn't that more like anarchism?
- Before agriculture people were like that, but as people settled down it created a class system. Then people got more powerful and such and states began to be created.
  
  During this time (Around 4000bce and 400ce) feudalism wasn't really a thing, but after the Western Roman Empire fell around 400ce the power vacuum it created lead to the creation of feudalism. This was because of several factors, but I can't remember them all right now.
  
  But money did exist even before the creation feudalism, since the Romans and the Egyptians did have money. Even in Mesopotamia currency was used. And even if money didn't exist trade was still being done with valueable things like resources and other commodities, which lead to those things becoming a de-facto currency.
  
  So basically pre-agriculture was like tribes that shared their stuff and such, but after agriculture not so much. Of course this isn't a one-answer-fits-all thing, since there are always exceptions.
  
  Sorry for the long ramble. I just got really into writing this thing. Also I could be wrong on some things, since I am writing from memory.
- Even in tribe, people did not share everything. Hunting weapons (means of manufacturing ) were most likely in personal possession. There was also rudimentary trade between the tribes. But as soon as real economy started to appear (and here I use the word “real economy” as system that requires cooperation of large number of people and labor separation) the means of manufacturing (wind mill, pack animals, etc) were mostly in private ownership, could be bought and sold. So, no, not communism.
Nobody is saying that communism is human nature either, but that it is the best system we could ever have.
- Questionable on both accounts. There are people who are saying this, and I am not sure that this is the best system that we (as in biological humans with our desires) could ever have. The experimentations so far (e.g. USSR) shows the opposite, that having more material incentive help humans to be more productive.