What are the most important inventions since flint tools and why?

Well I can speculate a couple of reasons. One would be our bodies' own mechanism for keeping in line with the earth's days, which is controlled by our optic nerve's exposure to daylight. This retrains our system each day, as earth's days have, over millennia, become longer, with the slowing of earth's axial rotation. While candle light is soft, & mimics the undulating light of the fires our forebears once slept around, electric light is stronger, harsher, and more like daylight. It is recommended, for those who have trouble falling asleep at night, that they minimize their exposure to bright electric light-- including even the blue light of a computer screen or smartphone-- for a number of hours before bed.

Another possible contributing factor is that candles are much more of a hassle than electric light. They don't illuminate as great a distance, so most homes, I imagine, were not kept fully illuminated, throughout the evening. Instead people would carry a lit candle with them, which requires one to be careful to not move so quickly as to put out the flame. Also, if one uses tapers, they frequently need changing. Thicker candles, however, are in continual need of trimming. As it takes so many candles to make a room well-lit (even when compounding their effect, through the use of mirrors & other reflective surfaces), unless one has servants to attend to this ongoing maintenance, I can see most people opting for dimmer than daylight surroundings, at night, rather than be tasked with all the candle-work. The expense, if one were to keep their homes brightly lit throughout, would also add up.

I never used a tallow lamp, so I'm not sure of their attributes, vis a vis candles & electric light. I would imagine, however, they might create soot. Did they produce any scent? At the very least, they necessitated the chore of keeping a supply of fresh tallow, always at hand. Having full light, at the flick of a switch, is just easier, which would encourage brighter indoor environments at night.

 

Yes, tallow lamps were filthy, smelly inefficient things but for medieval peasants who couldn't afford expensive candles, often produced and sold by the local abbey, they were the only choice. Tallow was just a by product of cooking meat so it would be readily available at next to no cost and the wicks could be made from any scraps of cloth or even hemp or sisal rope which was past its usefulness.
All these silly films with huge torches burning every few yards along a castle's walls were complete nonsense. I've visited dozens of castles in England and Wales and not once have I seen a wall bracket for torches or seen any mention of them in the literature.

 

Tallow was also used for candles but again they would have been dirty, smelly spluttering things used mainly by the poor. The rich didn't want their posh wall hangings and tapestries getting all sooted up.
Lamps would have been used in castles and fancy houses but they would have used a cleaner more refined oil than the peasants could afford.
Of course your fire place would have provided most of the light in your great hall or your tiny hovel.
Torches would have been incredibly smoky and quite the fire hazard used indoors. They don't burn for long either, unless you've got a hidden gas pipe in your studio set.

 

My favourite castle of all time, Beaumaris on Anglesey in Wales, has winding narrow passages inside its 20' walls which by day would only have been lit by light coming through the numerous arrow loops. People forget, or don't realise, that they would have been plastered and painted white though so even at night a single candle or lamp would have been plenty to illuminate your way to a defensive position or garderobe.

 

The most important invention - the internet.
Before the internet if you wanted to know how computer works, the difference between the aggregate and sum, byte vs char, CDMA vs GSM and much more – you had to spent hours in library – now it is a click.
On top of it can find tons of important information – that the earth if flat, lizard people and cannibals stay behind the Democratic party, the coronavirus is a Democrats hoax (which will disappear in April), the US elections were stolen and much, much more. Thank you Al Gore!

 

Computers are for nerds. I spend barely 12 hours a day on mine.

 

The pen (or the chisel/rock/thing)
Sure, the written word was great, but where would it have been without the tool used to write it?
When someone somewhere stood up on their hind legs and thought
'I'm going to write with this'
The thing they used, that; as great invention. The writing tool.
The leap, of writing something down, and using an object to write with.

 

OK then, I'll add the stick to the list of man's greatest inventions.

 

More like the rock.

 

One very important development which we have missed.
Trade.
Without trade the specialisations which moved us from simple farmers to civilisations couldn't have happened. You might have specialisation amongst small family groups or tribes where one person might be the potter or the flour grinder but trade allows us to spread ideas such as metallurgy by swapping precious metals such as tin and copper for other valuable products throughout the known world.
International trade goes further back and further afield than we used to think. The Amesbury Archer, circa 2300 BC found near Stonehenge had grave goods from central Europe. The Anglo-Saxon burial of King Raedwald unearthed at Sutton Hoo dating from the 6th or 7th century contained numerous small black beads now known to have come from Afghanistan.
Globalisation is nothing new folks and has in fact been a positive force in our development.

 

More like the concept of, seeing mark left by stick or rock, and then thinking...
I can use this stick or rock to make my own marks.
The invention of the writing tool.

 

Speaking for a select group, whomever inventing the current method of testing blood glucose has my heartfelt and eternal thanks. I could not imagine having to do this every day...

The History of Diabetes - Diabetes Center - Everyday Health

 

That would be glass knowing this thread, or modern medicine.

 

I could live without a great deal of 'modern medicine' (supporting a giant medical-industrial complex) but for that little lancet and strips....

 

Hmm, ''water taster'' would have been a particularly unpleasant job.

 

I still might be the root of your blood testing breakthrough.

Apparently the internet had to give way to Genghis Khan's pony express which then had to give way to the invention of the written word.

Couple of things about that written word thing...
It is the ability to get the word out further, but it's also the invention of the ability to be out lived by your words.

And, Genghis Khan's pony express of sorts took that written word further, but I still say the internet.

...
But without the concept of even having a writing tool, where can the written word or even the cave painting have gone?
No where, that's where, it'll never have even been without the thought to use something to make your own marks to pass a message on.

 

Some glass making experimental archaeology

 

Telescope
Psychology
Nylon

 

For fun... Current and future:

Dry cell batteries
High efficiency solar panels
Robotics
Artificial neutral networks
Fusion Engine
Chemotherapy
Organic agriculture
Transcendence (science of)
Environmentalism
Social anthropology
Urban design and planning

 

...Printing
Compass
Steam Engine

Spectrography
Quantum physics

 

Nice to have someone come in who obviously hasn't read the thread and only says one thing out of three that has already been mentioned.

 

Again, only two already mentioned.
I always have to point out that I'm only accepting the movable type printing press.
I don't think anyone has brought up the compass before, such an obvious one I don't know how we missed it.

 

You're a hard task master. Did you realise I actually skimmed as best I could and deleted a couple? Probably could have made a bit of better effort, but don't have time to read every word.

A pity you can't edit post after 15 minutes. You could have a running tally first post.

 

Alcohol.

 

I think you did a typo, or I misread. Lol. Hopefully you meant I did make some effort to read