These brand-new recreational logic puzzles provide entertaining variations on Gödel´s incompleteness theorems, offering ingenious challenges related to infinity, truth and provability, undecidability, and other concepts. Created by the celebrated logician Raymond Smullyan, the puzzles require no background in formal logic and will delight readers of all ages.The two-part selection of puzzles and paradoxes begins with examinations of the nature of infinity and some curious systems related to Gödel´s theorem. The first three chapters of Part II contain generalized Gödel theorems. Symbolic logic is deferred until the last three chapters, which give explanations and examples of first-order arithmetic, Peano arithmetic, and a complete proof of Gödel´s celebrated result involving statements that cannot be proved or disproved. The book also includes a lively look at decision theory, better known as recursion theory, which plays a vital role in computer science.
The PERFECT GIFT for anyone who loves a good head-scratcher - the original official puzzle book from the GCHQ team . . . Would GCHQ recruit you? Pit your wits against the people who cracked Enigma in the official puzzle book from Britain´s secretive intelligence organisation . . . -------------------------------- Odd word out The themes in the following words are identical, but totally different! Which is the odd word out in each case? a) ANGLE, BRING, CLAMP, DIRTY, EXACT, FIELD, GRASS, HEART, IMAGE, JAUNT b) ABBEY, BURST, COURT, DRINK, ENJOY, FOUND, GIANT, HARMS, IDIOT, JUMPY Identify Me My first is in a combine harvester, but not in a ploughshare. My second is in a pigsty, but not in a cowshed. My third does not exist. My whole is in a farmyard, but not in a jungle. Identify me. -------------------------------- GCHQ is a top-secret intelligence and security agency which recruits some of the very brightest minds. Over the years, their codebreakers have helped keep our country safe, from the Bletchley Park breakthroughs of WWII to the modern-day threat of cyberattack. So it comes as no surprise that, even in their time off, the staff at GCHQ love a good puzzle. Whether they´re recruiting new staff or challenging each other to the toughest Christmas quizzes and treasure hunts imaginable, puzzles are at the heart of what GCHQ does. Now they´re opening up their archives of decades´ worth of codes, puzzles and challenges for everyone to try. In this book you will find: - Tips on how to get into the mindset of a codebreaker - Puzzles ranging in difficulty from easy to brain-bending - A competition section where we search for Britain´s smartest puzzler Good luck! ´Fiendish . . . as frustrating, divisive and annoying as it is deeply fulfilling: the true spirit of Christmas´ The Guardian ´Ideal for the crossword enthusiast´ Daily Telegraph Looking for more ways to test yourself? The GCHQ Puzzle Book 2, a new collection of head-scratching, mind-boggling and brain-bending puzzles is out now!
`Dear God, what is it like in your funny little brains? It must be so boring.´ Can you pit your wits against the best and the wisest? Through these 200 puzzles and challenges, you´ll be able to elevate your powers of deduction, detection and general brilliance. From codes and sequences to perceptual and logic problems, there are puzzles for all levels, from beginner to expert. With explanations of how Sherlock (and hopefully you) arrived at the solutions, this official puzzle book is your chance to learn how to think like Sherlock. Step inside his mind palace, decipher Moriarty´s taunting clues and find out if you´re a match for the brains of 221b Baker Street.
The Penguin Book of Puzzles: Gareth Moore
A special book and CD edition of the bestselling Monkey Puzzle. ´´I´ve lost my mum!´´ Where is Monkey´s mummy? It´s not too much fun being lost in the jungle, and little monkey wants his mum. A kindly butterfly is keen to help, but they don´t seem to be having much luck and keep finding the wrong animals! But eventually, they find . . . Dad! It´s just as well that he knows exactly where mum is, and she´s waiting with a well-deserved cuddle. Monkey Puzzle is a clever, funny and charming tale from the unparalleled picture book partnership of Julia Donaldson and Axel Scheffler, creators of The Gruffalo. Monkey Puzzle Book and CD Pack features the classic story with a stunning redesigned cover and finish, and a story CD read aloud by actress Imelda Staunton, making it a must-have addition to the bookshelves of all Donaldson and Scheffler fans - big and small! Also available with redesigned covers are The Gruffalo, The Gruffalo´s Child, Room on the Broom, The Snail and the Whale, The Smartest Giant in Town, Charlie Cook´s Favourite Book, and A Squash and a Squeeze.