> catholic church has stood largely unchanged for the 1600 odd years
You have a very flexible definition of "unchanged" then. The Catholic Church pre-Charlemagne is going to be very different from Saeculum Obscurum-era, itself different from Investiture Crisis-era, itself different from the one familiar in the Late Medieval, different from Counter Reformation-era one. It's absurd to me that you think the first time it changes significantly is Vatican II!
> Ancient Egypt was already thousands of years old when Socrates harassed aristocrats in Athens.
My knowledge of Ancient Egyptian history is extremely poor, but what little I do know strongly suggests that considering it as a single stable form of government for thousands of years is even worse an error than claiming the Catholic Church was so stable and unchanging. Perhaps akin to saying that the Holy Roman Empire, the German Empire, the Weimar Republic, the Third Reich, and modern Germany are all one single country that has lasted for 1200 years (because they're all called Germany).
It's not 100% undisputed but most historians would agree that until conquered by the Persians in 525 BC, Egyptian history consists of 26 dynastic changes and 8 major distinct periods. Each dynasty of course usually had more than one ruler. Since we're talking about Socrates, then the slightly extended timeline of 33 dynastic changes (including 2 Persian, and 2 Greek), across 9 major and distinct periods, would represent pretty much the mainstream view that is supported by the available evidence, ending in its incorporation into the Roman Republic in 30 BC.
If anything, Egypt is one hell of a counter example of institutional stability. I would also make the pedantic quibble that the HRE never called itself "Germany" until the term was incorporated into part of its much longer official title in the late 1400s. English usage started in the 1500s. It's not to say that the concept of "Germany" or "Deutschland" didn't exist, but pre-Westphalia it's difficult to make truly apt comparisons to conceptualizations of states today, and the term equivalent to Germany was used, intermittently at that, from Charlemagne's death for the next 700 years somewhat like the status of Scotland or Wales within the UK today, as in, it coexisted with the HRE as an part but not considered to have referred to the whole until the HRE lost its non-German territories an that was pretty much all that was left.
You have a very flexible definition of "unchanged" then. The Catholic Church pre-Charlemagne is going to be very different from Saeculum Obscurum-era, itself different from Investiture Crisis-era, itself different from the one familiar in the Late Medieval, different from Counter Reformation-era one. It's absurd to me that you think the first time it changes significantly is Vatican II!
> Ancient Egypt was already thousands of years old when Socrates harassed aristocrats in Athens.
My knowledge of Ancient Egyptian history is extremely poor, but what little I do know strongly suggests that considering it as a single stable form of government for thousands of years is even worse an error than claiming the Catholic Church was so stable and unchanging. Perhaps akin to saying that the Holy Roman Empire, the German Empire, the Weimar Republic, the Third Reich, and modern Germany are all one single country that has lasted for 1200 years (because they're all called Germany).