Subject-wise, _The Years of Rice and Salt_ pushed all the right buttons for me - opening with a Journey to the West pastiche was always going to score it points, then there was a section set in Samarkand, quotations from Ibn Khaldun, and some deftly-drawn portraits of medieval China. I'm a sucker for a) cleverness, and b) well-crafted settings outside the pseudo-medieval fantasy norm, and this book hits both markers. So I wanted desperately to like it. In some ways, I did.
But there are two fundamental flaws, in my opinion. Firstly, the device of reincarnating the same set of characters fails; none of said characters are distinctive or memorable enough from life to life, and so end up being effectively 'new' in every section/time period. There's little chance for the reader to develop any emotional investment before the section ends and the whole thing starts again, and it becomes difficult to truly care.
Its second problem is, curiously, its lack of scope and vision. While the novel's stage is an entire world over six or so centuries, the device of keeping the characters together in each incarnation means that each section concentrates on one small area, robbing the narrative of the benefits of multiple, varied viewpoints. The scale is narrow rather than epic, and the action tends to get bogged down in details. This would be fine if the details were used to build character or illuminate the larger picture - the themes of this alternate, Europe-less world - but a lot of it reads like navel-gazing.
Many of the truly interesting implications are skipped over in favour of scientists ahead of their time discovering exactly the same things at almost exactly the same time their counterparts did in the non-fictional world, as if Robinson feels that certain universal boxes must be checked along the road to 'development', whatever the structure or imperatives of a society. (Meanwhile, literature, drama and art get short shrift). Often even the same words are used - I know little about the history of scientific thought, but would a world whose development was shaped by Arabs and Chinese still have used so many Greek and Latinate constructions to label their deeds? (okay, so he can get away with Greek, Islamic scholars were big on Greek. but still).
While there are glimpses of greater things - Buddhist attitudes and beliefs are used very well, and the different trajectory of American history is intriguing, but frustratingly underexplored - Robinson seems to be more interested in following a pretty conventional path. Perhaps dictated by his reincarnation device, he surrenders to the temptation to work towards a conclusion, as if human history could have ultimate purposes or goals. (I imagine one could argue that this reflects the world-view of those he writes about, but intentional or not it doesn't work!). Ultimately, this is too big a topic for one novel, and in trying to cover everything the author spreads himself too thinly, and ends up short-changing a fascinating world.
Despite these caveats, this remains a hugely enjoyable and memorable read, a rich tapestry of cultures and ideas rarely explored in genre fiction. Worth a look.