I'm going to be reading The Great Transformation and Red Mars for a little while yet, I suspect.
As I said before, Karen Armstrong's thesis (not originally hers, but developed in great detail in The Great Transformation) is that the revolutionary spiritual philosophies she exemplifies with the figures of Confucius, Buddha, Socrates and Jeremiah, represent a paradigm shift in global (or at least Eurasian) thinking about religion, and thus in the consensus definition of what it means to be human. The main difficulty I have with this so far is the lack of connection she draws between the histories of China, India, Greece and Israel.
China's clearly the odd culture out here, as there are visible links between the remaining three: the first-millennium-B.C.E. Greeks and North Indian Aryans shared common (and relatively recent) Indo-European roots, while Israelite and Greek spiritual culture were strongly influenced by the common myth-systems of the pre-classical Mediterranean and Middle East. All three peoples later had common dealings with colonial Middle Eastern superpowers, most notably the Persian Empire and Alexander the Great.
However, as I understand it, contemporary China was a great deal more isolated, and isolationist. Although only rarely and sporadically unified, the people of the North China plain in the first millennium B.C.E. mostly dealt with one another, or at most with neighbouring peoples whom we'd also identify today as Chinese -- rarely travelling, under no threat from foreigners and warring only against one another. Aside from some trade with neighbours including India (the route by which Buddhism eventually arrived in the first century B.C.E.), ancient Chinese culture was monolithic and self-sufficient. Nor was the era of Chinese history which Armstrong takes as her starting-point -- the culture of the Shang Dynasty -- similar in any notable way to that pertaining in Mycenaean Greece, pre-Biblican Canaan or tribal Punjab.
Thus one might see Jeremiah, the Buddha and Socrates responding in the seventh, sixth and fifth centuries B.C.E. respectively to broadly similar (and distantly connected) social upheavals which led them to question contemporary belief-systems (Yahwism, the Vedic religion, Olympian polytheism) which in turn had originally been revisionist responses to yet more ancient polytheisms with a common ancestral background. The contemporary Chinese sages, however -- Confucius, Lao Tzu, Zhuang Zi et al -- weren't responding to anything that hadn't been Chinese for millennia.
I haven't read ahead, so it's possible that Armstrong's saving up her explanations for the last chapter. As far as I can see, though, if she really wants to justify these supposed simultaneous revolutions in thought (and let's not forget that Jeremiah and the Buddha, say, were roughly as contemporary with one another as Newton and Einstein) as anything more meaningful than coincidence, then her options are limited.
Unless she posits: a) a level of global travel and communication during this era that there's really no evidence for, or b) some kind of large-scale global influence (climatic or epidemic, perhaps, although she's shown little interest in those so far), she'll have to fall back on c) a load of mystical bollocks ("It was a quantum leap in human evolution", "God moves in mysterious ways", "It was Gaia achieving self-consciousness", etc). I can't really see her doing any of those... but if the conclusion's going to be "It was all a really big coincidence", then I can't altogether see the point of the book either. Oh, well.
Meanwhile, Red Mars is also exploring the gradual, large-scale tectonic changes which turn ordinary people adapting to a changing environment into an entirely new culture, and doing so at a very, very leisurely speed. At this rate I'm hoping I'll be finished with the trilogy by Christmas. Thank heavens for the lovely, brief short stories in Short Trips: Transmissions.
Incidentally, apropos of my tag for Robinson-related posts... when my fellow Bernice Summerfield authors Lance Parkin and Mark Clapham were writing their take on Martian history, the only mildly parodic Beige Planet Mars, their original suggestion for a back-page tagline -- veoted by Virgin -- was "Danger, Kim Stanley Robinson!". Which, in the absence of any humour in Red Mars, at least makes me smile wryly.