Science-fiction (sf) writers have been known to gripe about the extremely short window of obsolescence on speculative works – one that seems to be getting shorter proportional to the acceleration of technological change. I can sympathize. The same is true of criticism that takes such texts, and the conditions they respond to, as its objects. The relatively short span of time elapsed between this book's writing and its publication has witnessed major historical events, and in preparing my manuscript for print I am startled at how many of its details no longer seem to reflect the reality of the present moment with quite the same urgency they did even a year or two ago.

Since the bulk of Singularities was written, the ongoing economic crisis – precipitated in part by forces with which the book attempts to reckon – has toppled banks, destabilized currencies, and shaken the foundations of nation-states. Protest movements engendered by, organized around, and deriving much of their energy from newly ubiquitous streams of information have brought down regimes. Others may yet follow, and it remains to be seen what will emerge in their place. Meanwhile, an apparent increase in the frequency and intensity of natural disasters has made it increasingly difficult to ignore the evidence that our planet's climate is changing in profound and perhaps irrevocable ways, contributing to further economic and political instability in the process. Particularly in this last respect, the overall disposition of world events appears rather more ominous than it did at the time I began writing – yet at the same time, in its sublime indeterminacy, all the more replete with possibility. For even amid these developments, which range from ambivalent to outright disturbing, we have discovered scores of new planets, charted Martian riverbeds, and found the Higgs boson. It seems premature to conclude that the century to come will not be at least a little bit awesome.

The facts on the ground will continue to change, but the larger historical trajectory to date holds with what is described in these pages. Even so, I regret that I have not been able to substantially address cultural developments that transpired, or came to my attention, too late for more than a cursory mention at this stage.