The Rule of Four, Caldwell & Thomason

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The concept of the book - the decoding of secret ciphers in a little known Renaissance text - sounded very Da Vinci Code to me, and I almost took a pass on it, not being a fan of conspiracy theory-type suspense, but I ended up totally enjoying every minute of this book!

If you are looking for a murder mystery, that thread is minor, but there's so much else that's brilliant and heartfelt in this intellectual head-trip of a book which skips backwards and forwards in the telling.

From Chapter 24:

"In a world where half the villagers always lie and half of them always tell the truth; where the hare never catches the tortoise because the distance between them shrinks by a never-collapsing infinity of halves; where the fox can never be left on the same bank of the river as the hen, or the hen on the same bank as the grain, because with perfect regularity the one will consume the other, and nothing you can do will prevent it: in that world, everything is sensible but the premise. A riddle is a castle built on air, perfectly habitable if you don't look down...."