Many useful technologies like concrete and surgical instruments had to be reinvented as late as the 18th century. What I don't understand is how these were not kept by the Byzantines, or were they still used but hopelessly obscure to be noticed?
It was partially because of the scale of cultural losses in early Christianization, partially because the ERE perpetually tended to shrink in size, and partially because Islam was the center of technological progress on a classical foundation in the "Dark Age", not Eastern or Western Christendom. The ever-shrinking ERE increasingly lost the economic base to use that technology and Muslims developed superior social infrastructure and military organizations that rendered this technology obsolete by improving on it.
This.
The ERE in its healthy, vigorous days did preserve a lot, however. What had to be reinvented in the West shouldn't be taken as revealing of what was maintained in the ERE.
Of course those healthy, vigorous days pretty much ended with the Heraclius-Khosroes II War, and the need to perpetually re-invent itself kind of put a crimp on how much technological innovation the ERE could reasonably do. It did preserve more than the West, and this is one reason that the Eastern half of the Empire preserved itself where the West did not (the other is that the ERE held onto the seat of the 5th Century Empire's recruiting base, preserving military power while also holding onto Egypt, the larger Empire's breadbasket).
Of course those healthy, vigorous days pretty much ended with the Heraclius-Khosroes II War, and the need to perpetually re-invent itself kind of put a crimp on how much technological innovation the ERE could reasonably do. It did preserve more than the West, and this is one reason that the Eastern half of the Empire preserved itself where the West did not (the other is that the ERE held onto the seat of the 5th Century Empire's recruiting base, preserving military power while also holding onto Egypt, the larger Empire's breadbasket).
I blame Khosrow II. The bugger was no help in Persia either. Just a warmonger with mediocre military talents blowing the entire treasury on campaigns that were largely unsuccesful. Not to mention that Heraclius repaid what he did in Syria by turning Northern Mesopotamia into a bad place.
How well/badly was that repaired later?
It was made pretty again under the Arabs along with most of the border regions. Those eras were so devastated after years and years of warfare, as they had been for centuries, that they had little economic value.
What most people don't realize is just how far back that the technological and craftsmanship decline began. For instance the Baths of Zeuxippus which were damaged during the Nika Riots couldn't be repaired because there simply wasn't anyone who had the knowledge how.
Wikipedia talks a little bit about it http://en.wikipedia.org/wiki/Baths_of_Zeuxippus one of my books goes into more detail about of the problems but I'll need to sift through them to find the right one.Source? Not arguing, but this is outside the area I'm most familiar with, so it would be interesting to hear more about it.
I do know that the Empire managed to keep up with changing times in regards to the areas needed to stay prosperous and defend itself, so it couldn't have been too damaged.
Wikipedia talks a little bit about it http://en.wikipedia.org/wiki/Baths_of_Zeuxippus one of my books goes into more detail about of the problems but I'll need to sift through them to find the right one.
Interesting.Another example is The Nemi Ships which among other things had metal working that wasn't match or beaten till the 1800's and pumps that weren't seen again till the middle ages. Its not that the later Roman Empire/Byzantine Empire was technologically inept quite the opposite in fact. Its just the fact that over time techniques and precursory knowledge were lost due to a variety of reasons which made old technology no longer viable. Hell we have the same situation today for instance if you wanted to rebuild some of the more impressive cathedrals/churchs using period authentic techniques finding people with the practical knowledge would be next to impossible. While a bit off topic is the even sadder fact of the technical challenges we'll need to revist to put a man back on the moon. The same thing happened in Rome and Constantinople only to a much greater degree since so many trade secrets were only passed down from master to apprentice and not written down so the more advanced or valuable a skill set or piece of knowledge was the more likely it was to be lost to the whims of fate.
The steam engine took so long to become practical because earlier the material sciences simply weren't up to snuff metallurgy especially. It's kind of like claiming that only reason that the Tang dynasty didn't make it into space despite having rockets is because of their form of government.I've been studying this, and believe the answer's unconstitutional monarchy. After the Caesars, the Senate was just for show. Unchecked monarchy has a pretty lame record in many ways, including tech. That's a third because less than half of people chosen by birth are good, a third because too much money centralizes to the king and other aristocrats, and a third because kings are paranoid of rivals arising, and so hard on the smart.
Notice that Saudi Arabia's pretty low tech, too, for the same reasons. The UK was slow, too, until, hmm... when it got a a constitution, and then some actual freedoms.
And so, that's why it took a millenium and a half for the steam engine to go from Hero's prototype to a machine doing work in the returned freedom of the English and Dutch Renaissance. I've also come to believe that the habit of looking at evidence was lost from misuse, because the Muslim Caliphate's Avicenna had to rediscover it (and then couldn't spread it enough, from bad luck).
The steam engine took so long to become practical because earlier the material sciences simply weren't up to snuff metallurgy especially. It's kind of like claiming that only reason that the Tang dynasty didn't make it into space despite having rockets is because of their form of government.
Not to mention a fair amount of the more impressive bits and piece required such a high level of skill having blueprints would only take you so far.Interesting.
Sounds like something where even writing it down wouldn't necessarily help - it is entirely too easy to imagine having written copies kept, but no one remembering where. Or with them written back in the distant enough past, those copies suffering the fate of all matter and not being replaced - and by the time anyone realizes it, no one remembers it well enough to write it down.
To a large degree yes. You also have situations where technique A might be superior but technique B is cheaper and more often than not "good enough" and eventually A just disappears because there simply isn't the demand. Or where you need to know how to do A, B, and C to make or build D and eventually due to various circumstances the knowledge of one or more becomes scares decreasing the value of the others and so on and so on.Or is it just all such societies are going to "forget" a lot, even if new methods that work sufficiently well for equivalent designs develop for many areas?