What was the greatest invention of all time at the time of its conception?

The wheel, fire, the stirrup, gunpowder, the crossbow.

The Vulcan Science Directorate has determined that In my opinion the greatest ‘invention’ at its time was the Special and General Theory of Relativity, followed by Quantum Mechanics, the Theory of Evolution, Atomic Theory, Germ Theory. Electrical theory and classical mechanics.

internal combustion engine

The printing press. This had gigantic impact on society within a few generations that has lasted for centuries.

Vaccines.

I agree with @Mamradpivo, Johannes Gutenberg’s printing press.

Other than @gailcalled, these are some fairly recent inventions. Are recent inventions really the greatest a ha moments? I think I like @gailcalled ‘s answer “fire” the most so far. It certainly had to have been a vastly profound moment in history, even though it was more of a discovery of an entity which already existed.

And yes, this question was inspired by the popcorn which I’m currently eating. I can just imagine the first person who made popcorn, and the look of surprise when it popped up into a tasty treat. XD

Pop Rocks and still one of the greatest!

My guess is Archimedes when he discovered displacement.
He even had the perfect word for it

The germ theory of disease.

refrigeration

Dirt. Pretty much can’t do anything without dirt.

Oh Ok, Plastic. Err um, also Space Aged Materials. Otherwise the infomercial would never have been born,

Refridgeration.Now,fetch me a cold one!

Oh. Trebuchets were pretty cool.

Disobedience.

Type “greatest invention” (or some variation of) in the search bar. You’ll find a great many answers on the great many versions of this question.

I don’t know if it’s the greatest, but birth control in modern form is up there.

@rebbel My daughter Rachel invented disobedience in 1983.

@dpworkin I thought Eve was some years earlier then your daughter, but i’m sure she made her proud ;-)

I can only vouch for the invention I was there to see.

I’m pretty sure it was sliced bread. It inspired it’s own phrase, which is more than most inventions can hope to achieve.

Fire wasn’t an invention. It was a discovery. It existed long before we figured it out.

Medicine was probably the greatest invention.

I wonder who was the first person to look at a cow’s utters and go, gee I wonder what happens if I yank on those.

It’s from Calvin and Hobbes, but I guess it’s not an invention.

Therefore, I choose any invention that involves a phallus shaped object sticking into a hole, like uh…“Trails off.*

@dpworkin I was going to say penicillin but then I thought, no, that’s not an invention. @Natural I think if we include research, penicillin has to be a great one.

The internet is the most significant invention of our lifetimes thus far.

And of course we have Al Gore to thank for that~

That would be Tim Berners Lee and others though Al Gore did give some money to the project.

It was Hal working behind the scenes for decades.

Beer.

@loser I really wonder now about the evolution of beer. And I’m thirsty.

Some guy named Charlie apparently.

Beer is sometimes given credit for the beginning of human settlements and the domestication of cats. Settlements grew up around the granary, and cats also proved their worth by controlling granary rodent pests.