>I can make this argument about anything you listed as being "progress" from 1909-1959. People who now fly could have driven, or taken the train, or rode on horseback. Flying is just faster, right?

Flying is categorically vastly different than ... taking the train. So is space flight.

>The jet engine is just an evolutionary change over the turboprop.

Um, the jet engine came before the turboprop, so, in fact, no. The jet engine was indeed an improvement over other kinds of heat engines; not only were they more efficient (which is why they're used in energy production, and, say, turboprops), they enabled vastly faster and safer flight, are vastly more reliable (which is why they're used on ships and in prop driven planes instead of piston engines), and are very, very physically different from more complex internal combustion engines. It's not the atom bomb, but there sure aren't too many commonly used things invented between 1959 and the present which have increased human power over nature the way the jet engine did. Even if you put the cell phone in the same class of improvement as the jet engine (I don't, but I'd concede the point for the sake of argument): that's one thing.

> The atom bomb is just a really big bomb, right? Couldn't you just drop 10,000 equivalent bombs?

Of course not: this is ridiculous. With 10,000 nukes you could pretty much wipe out civilized life. It is categorically vastly different. It is a factors of 100000 difference in power available to human beings. There has been no such change in the most recent 50 years which can compare to the bomb at all. And that's just one of the cataclysmic inventions of the 1919->1969 years.

> In 1959, computers did almost nothing for almost nobody. You are taking an entire half century of advances in computing and saying they are irrelevant because you can draw some "fundamental" line in 1959 that everything was done before. But if we still had 1959-level computers our society would be, to use your words, insanely different.

You really need to read up on your history. In 1959, computers were doing: atomic weapon and nuclear reactor design, networked atomic weapon defense (the SAGE system was in place and operational -and ran until the 1980s, FWIIW it also had a graphical user interface, not conceptually unlike that on your nerd dingus), running large corporations, guiding missiles and other autonomous vehicles, running banks, it was being used for early AI experiments, it was being used in engine design, climatology, it had huge impact on physics and engineering and pretty much everything else. It made things possible which were simply impossible in the 1919 date 50 years prior. The things we've done since then in computation are obviously progress, and important, but there have been no huge category changes such as the invention of the computer.

> So what makes 1959-2009 "not progress"?

I never said those years were not progress. Fourier transforms, coding theory and so on were great leaps forward that made new things possible. But they were nowhere near the leap forward that the invention of the computer was in the first place. The invention of the computer happened in the years before 1959; it really did change everything in a categorical way. I can't think of a single thing since 1959 which compares to the invention of the computer. Or antibiotics. Or the human harnessing of atomic energy. Or space flight.

> I venture that if we transported you back to 1969 you're be complaining about the lack of progress since 1919 too...

In 1969, absolutely nobody could make the argument that antibiotics, the atom bomb, computers, space flight, (autonomous) guided missiles meant there was no progress since 1919. Most people in 1969 fully expected we'd live in the world of "2001 a space odyssey" by 2001; with sentient computers, nuclear interplanetary flight, space tourism, moon bases, routine hypersonic flight, suspended animation, video calls (which didn't become routine until ~ 10 years later). Lots of people thought Clarke/Kubrick were too conservative in their predictions! They did get flat screens right though!

The reason everyone thought the world would be so ... futuristic in 2001 -futuristic to the point these innovations are now considered to be ridiculously optimistic, is because the years between 1919 and 1969 (to say nothing for 1869->1919) had so much ridiculously and egregiously giant progress. That's my point! Progress has inarguably slowed: the end. Denying it is silly. If you're not denying it, well, I'm glad we agree! If you agree and are saying you don't like my arguments; which arguments would you make?