Tremendously heady book, but not one for everyone. It must be read very slowly, and with a dictionary handy (638 pages). Prepare yourself for pages and pages of sentences like (selected at random) "It seems impossible: twenty can't be sufficient word-hoard to engineer the tens of thousands of complex chemical reactions required to make a thing live. But lying in bed under my arctic nightlight, carrying out the simple arithmetic, I see how the abject simplicity of protein produces more potential than mind can penetrate." Now having said that, the book is beyond fascinating. Loved the main characters, especially Jan. It contains huge nuggets of profound thought if you can read it ever-so-slowly and digest it and stick with it. Walk away from it when you need to. You'll constantly want to underline something to remember and revisit it later and will find you don't want to mess up the book with ink. Don't skim it. You'll miss the connections. And that's the all.