Not Till We Are Lost

Not Till We Are Lost is the fifth Bobiverse book by Dennis Taylor. I’ve been following these books for years. Although there’s usually a delay in reading new releases because they’re initially exclusive to Audible. I do listen to the occasional audiobook, but most of my reading is Kindle editions. Thankfully they subsequently get released under Kindle Unlimited, which is nice.

The Bob in these books starts out as a software engineer in life who dies in an accident, and wakes up in the future to discover he’s now an uploaded mind and forced by the reigning theocracy to be the control system for a self replicating Von Neumann probe. He is barely launched before a devastating war desolates the earth. He explores other solar systems and makes copies of himself, some of which return to Earth to help the remaining human populations migrate to other worlds. In the meantime his replicas encounter other alien species, both hostile and friendly, and have a variety of adventures.

The stories are told in first person, with each chapter from the view of a particular replicant. Each replicant has a unique name, and there is “replicant drift” with each copy, leading each replica to have a slightly different personality. Initially the replicants are all recognizably Bob, but as the series progresses, the drift leads to major differences, and conflict.

Initially this is sort of hard sci-fi, with interstellar travel taking years. The “sort of” refers to the fact that the propulsion system of Bob’s ship is a type of reactionless drive. As things develop, the Bobs figure out how to communicate with each other faster than light, allowing an interstellar community to develop. And the reasons for the “replicative drift” are thought to involve quantum entanglement.

In this latest book, a group of Bobs, called the “Skippies”, are trying to create an artificial intelligence, something that, despite the success of mind uploading, has eluded human science. But in the fourth book, an alien AI is discovered, who turns out to be friendly, and provides advice on how to build AIs. Except in this book the Skippies cut corners, which leads the AI, named “Thoth”, to behave in ways that, at least on the surface, seem resonant with all the typical tropes of a dangerous AI.

At the same time, a couple of Bobs are exploring toward the galactic center of the galaxy, and come across a network of wormholes, and a highly advanced civilization that appears to be completely abandoned, although a lot of the automation in that civilization continues to work. They spend the book resolving the mystery of what happened.

There are also rising tensions with human populations, with growing resentment against the Bobs and other replicants, while the theocracy that had originally enslaved Bob’s mind is making a comeback. And there a side adventure with one of the Bobs and his wife as they use avatars to interact with another alien species, one that looks like human sized dragons.

This is a fun book and I recommend it, although I strongly suggest starting with the first book of the series.

I do have a few nits.

These books have never had tightly structured plots, with many of the threads meandering over time. In the early books, it didn’t feel like too much of an issue. The concept was fresh and it was an interesting exploration of the various implications. But I felt it in this one. It seems to take the story a long time to really get going, and some of the side threads felt pretty tedious.

I also could have used a bit more recap about all the various situations, developments, and technologies from the earlier books. Most of these are just referred to by name with the reader expected to remember the details. I read the first three books in 2017, and the fourth in 2023. I don’t have time to reread the whole series every time a new book comes out. Certainly some authors take this too far, and burn too much space constantly reminding us about everything, but having brief refreshers at least once in a book for relevant situations is a lot easier on the reader.

Finally, without getting into spoilers, the explanation for the disappeared civilization felt improbable. Not that I don’t believe it can happen, just that the idea of it developing at a point in cosmic history right when we might be able to do something about it strikes me as a little too convenient. Of course, this is fairly common in sci-fi, but it tends to briefly throw me out of the story.

All that said, if you enjoyed the earlier books, you’ll likely enjoy this one. And I definitely recommend the series overall. Have you read any of it? If so, what did you think?