‘What do you really know about the past?’ he asked. ‘How can you know what really happened? Are you so certain of what you have experienced that you can say: Thus it truly was and not otherwise? Think hard about it! I assert that only what is told is real. And even that for only a brief time.’

The Cusanus Game by Wolfgang Jeschke is an interesting newer addition to the time travel novel. It is a weighty book that touches on history and time, philosophy, quantum physics and string theory, and climate change.

The bulk of the book takes place in 2052. A nuclear disaster on the French-German border has made a large segment of northern Europe uninhabitable. Climate change is forcing the migrations of millions of people from the coasts and from areas that are fast becoming desserts. The world is in the midst of societal instability and crumbling governments. Terrorist groups spring up to protect the borders against immigrants or demand old people die so the young and unemployed can get jobs. Most people are just trying to get by and live their lives as best they can.

Domenica Ligrina is just completing her university studies in botany when she is contacted by a mysteries group affiliated with the Pope. Domenica is offered a job in which she can put her botanical knowledge to work in saving the world. It is all very hush hush, and she and a few of her friends from university go through a long and rigorous interview process at the end of which they must decide, without fully knowing what is expected of them, whether they will take the job or not. Domenica signs up; she is curious, she wants to work, and she has nothing to lose.

It slowly becomes clear that she has been recruited to be a time traveler. She will be sent back to 1450 Europe on a mission to collect plants and seeds that have gone extinct and bring them back with her to the present. Her friend Renata will be doing the same. But not all travelers collect plants. While undergoing training and preparation in Venice, she meets Frans who is an expert in architecture and has been traveling to learn about and bring back samples of, the various types of woods used in the foundations of Venice. Venice is rotting and this knowledge will allow the nanobot technology to molecularly repair the wood that holds the city up.

But what is the Cusanus Game? This refers to a game created by Nicholas of Cusa. The game is played on a large (5 feet x 5 feet) wooden board. On the board are concentric circles marked 1-9 with the center unnumbered. The object is to toss a ball about the size of an orange as close to the center circle as possible. But the ball is not perfectly round and the board is not flat. The players cannot aim directly for the center and no two throws will ever be exactly alike. The game is meant to be unpredictable and teach the players how to accept failure with good humor. The center is also meant to represent Christ and teaches that we cannot reach him directly because we are flawed, but if we persist, we will eventually get close.

Domenica’s story is like the Cusanus Game. She starts by aiming directly at her goal but goes far astray and eventually learns that her goal was not what she thought it was to begin with. When she finally figures this out she makes a great discovery about herself and the world, knowledge that was there all along but she was unable to see it because she was aiming at the wrong thing.

This being a fat and heady book, I have left out much. It is good science fiction. Well written and heavy on the science. If you have read Stephen Hawking or Brian Greene you will do just fine with the physics in the book. But if you don’t know anything about string theory or branes you can still read the book but will have a bit of trouble with the science. And there is quite a lot of science often laid out in loving detail.

It will also help you if you have knowledge of different theories of time travel and what one can and cannot do in the past or the future. It is not required that you have read other time travel scifi books, but it helps. Because things get, as my favorite Doctor says, timey-wimey. You will eventually come to a chapter that makes you stop and wonder if you haven’t read it before. And you will page back and find that yes, you did read a chapter just like this one about 70 pages back. But as you keep reading this new chapter which is going along word-for-word like the already read one, you will notice different details crop up that suddenly change what happens. Such chapters occur several times and it is really fascinating how each small change causes a deviation in the outcome.

For a fat, heady book, it moves along at a pretty good clip. There is a train journey in the middle that kind of bogs down a bit but after that the pace picks up again and fairly races to the end. The book was published in Germany in 2005 and just translated and published in English in 2013. I don’t know what took so long, but I am glad I got to read it.