150 pages, dozens of
illustrations. Perfect for kids 8+ to read on their own, or 5+ as a bedtime story.

All digital editions are DRM free.

I feel I should warn you.

No computers will be found in this book. If the idea of a computer science book without computers upsets you, please close your eyes until you’ve finished reading the rest of this page.

The truth is that computer science is not really about the computer. It is just a tool to help you see ideas more clearly. You can see the moon and stars without a telescope, smell the flowers without a fluoroscope, have fun without a funoscope, and be silly sans oscilloscope.

You can also play with computer science without... you-know-what. Ideas are the real stuff of computer science. This book is about those ideas, and how to find them.

Chapter 0: Mostly Lost

Lauren Ipsum had been lost in the woods all morning. The poor girl didn’t know where she was or where she was going...

Chapter 1: A Hidden Ally

“It’s only logical. First you learn to talk, then you learn to think. Too bad it’s not the other way round...”

Chapter 2: Sense and Sensibleness

“I put little ideas together to make bigger ones. Then I put those ideas together to make even bigger and bigger ones! And then I put my name on them. You shouldn’t let any ideas escape without a name...”

Chapter 3: Rounding Error

It was hard to concentrate with the birds singing and Xor screaming, but Laurie waited again, trying to see a pattern...

Chapter 4: What the Tortoise Said to Laurie

“I accept. Experiment is always better than mere Theory,” Achilles said. “And an impartial judge sounds wonderful, especially when she already agrees with me...”

Chapter 5: Welcome to Symbol

“If I have it, I know it, but if I don’t you can’t tell me, and you can give me a hint only if I set it up earlier!” This certainly was very good security! Think, Laurie, think!

Chapter 6: A Tinker's Trade

“...everyone develops their own style. You can put little ideas together to make big ideas. Or you put two ideas side-by-side and compare them. Or you start with big ideas and take them apart...”

Chapter 7: Read Me

“Did you know that kids in Finland start reading when they are only twelve months old?”

Chapter 8: More Than One Way To Do It

“Instead of looking for an answer that fits your problem, imagine an answer and look for a problem...”

Chapter 9: Don’t Repeat Yourself

“An Axiom is a rule that you pretend is true even if you don’t know why it’s true...”

Chapter 10: A Well-Timed Entrance

“If the start of your name isn’t on the List, there’s no reason to keep looking for the rest of it, now is there? It’s only logical.”

Chapter 11: A Fair Exchange

“Money made of paper? How strange! They are very pretty, but I’m sorry to say they are worthless here...”

Chapter 12: An Improbable Twist

“Lauren Ipsum, you are under arrest for Attempted Mythology, Counterfeiting Fair Coins, two counts of Impersonating a Composer, Hacking in the Third Degree, and Miscellaneous Mopery With Intent to Creep...”

Chapter 13: The Game of Life

“You should always know why you are doing something, and not just because someone told you to do it...”

Chapter 14: In The Abstract

“Algorithms don’t just happen in turtles and ants and coins. They also happen inside your head, and those are the hardest to get right...”

Chapter 15: Cleverness When It Counts

She needed an Approval from Euripides so she could get one from Darius, use that to get one from General Case, to be signed and countersigned by Basil and Anton. There was something familiar about this Byzantine chaos. Something Hugh Rustic had told her...

Chapter 16: A Change of Plan

“Clear the decks! Empty your minds! Brainstorm! I want new ideas!”

Chapter 17: Chasing Elegants

“There’s no need to use a big, complex idea when a small simple one will do.”

Chapter 18: Many Hands Make Light Work

“Sentences are made of words, and words are made of letters, right? In the same way, we make letters out of FLIPs and FLOPs

Chapter 19: Branching Out

“Every path forks off from another path,” Tortoise said. “One path becomes two, becomes four, eight, sixteen, and so on. After twenty-four forkings there are over sixteen million different paths.”


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