I am still digesting this book — I know that I liked it a lot, and I think it managed to succeed at almost every level besides having more-than-workmanlike prose. It serves as a great assemblage of metaphors, as a gripping murder-mystery, a terrifying horror film, and a deep question about what "reality" means and why the "real" matters.

★★★★

Highlights

“A spray can of Ubik,” the girl answered, “is a portable negative ionizer, with a self-contained, high-voltage, low-amp unit powered by a peak-gain helium battery of 25kv. The negative ions are given a counter-clockwise spin by a radically biased acceleration chamber, which creates a centripetal tendency to them so that they cohere rather than dissipate. A negative ion field diminishes the velocity of anti-protophasons normally present in the atmosphere; as soon as their velocity falls they cease to be anti-protophasons and, under the principle of parity, no longer can unite with protophasons radiated from persons frozen in cold-pac; that is, those in half-life. The end result is that the proportion of protophasons not canceled by anti-protophasons increases, which means—for a specific time, anyhow—an increment in the net put-forth field of protophasonic activity… which the affected half-lifer experiences as greater vitality plus a lowering of the experience of low cold-pac temperatures. So you can see why regressed forms of Ubik failed to—”

Joe said reflexively, “To say ‘negative ions’ is redundant. All ions are negative.”

We are served by organic ghosts, who, speaking and writing, pass through this our new environment. Watching, wise, physical ghosts from the full-life world, elements of which have become for us invading but agreeable splinters of a substance that pulsates like a former heart.