# Philosophy and Fun of Algebra

PHILOSOPHY AND FUN OF ALGEBRA

Works by

MARY EVEREST BOOLE

Logic Taught by Love. 3s. 6d. net.

Mathematical Psychology of Gratry and Boole for Medical Students. 3s. 6d. net.

Boole's Psychology as a Factor in Education. 6d. net.

The Message of Psychic Science to the World. 3s. 6d. net.

Mistletoe and Olive. 1s. 6d, net.

Miss Education and her Garden. 6d net.

Philosophy and Fun of Algebra. 2s. net.

C. W. DANIEL.

The Logic of Arithmetic. 2s.

CLARENDON PRESS.

PHILOSOPHY & FUN OF ALGEBRA

BY

MARY EVEREST BOOLE

AUTHOR OF

"PREPARATION OF THE CHILD FOR SCIENCE," ETC.

LONDON

C. W. DANIEL

11 CURSITOR STREET, E.C.

909

To

BASIL AND MARGARET

My Dear Children,

A young monkey named Genius picked a green walnut, and bit, through a bitter rind, down into a hard shell. He then threw the walnut away, saying: "How stupid people are! They told me walnuts are good to eat."

His grandmother, whose name was Wisdom, picked up the walnut peeled off the rind with her fingers, cracked the shell, and shared the kernel with her grandson, saying: "Those get on best in life who do not trust to first impressions."

In some old books the story is told differently; the grand-mother is called Mrs Cunning-Greed, and she eats all the kernel herself. Fables about the Cunning-Greed family are written to make children laugh. It is good for you to laugh; it makes you grow strong, and gives you the habit of understanding jokes and not being made miserable by them. But take care not to believe such fables; because, if you believe them, they give you bad dreams.

MARY EVEREST BOOLE.

*January* 1909.

CONTENTS

CHAP. | PAGE | |

1. | FROM ARITHMETIC TO ALGEBRA | 9 |

2. | THE MAKING OF ALGEBRAS | 15 |

3. | SIMULTANEOUS PROBLEMS | 19 |

4. | PARTIAL SOLUTIONS AND THE PROVISIONAL ELIMINATION OF ELEMENTS OF COMPLEXITY | 23 |

5. | MATHEMATICAL CERTAINTY AND REDUCTIO AD ABSURDUM | 26 |

6. | THE FIRST HEBREW ALGEBRA | 29 |

7. | HOW TO CHOOSE OUR HYPOTHESES | 37 |

8. | THE LIMITS OF THE TEACHER'S FUNCTION | 46 |

9. | THE USE OF SEWING CARDS | 51 |

10. | THE STORY OF A WORKING HYPOTHESIS | 55 |

11. | MACBETH'S MISTAKE | 61 |

12. | JACOB'S LADDER | 67 |

13. | THE GREAT X OF THE WORLD | 69 |

14. | GO OUT OF MY CLASS-ROOM | 73 |

15. | √-1 | 77 |

16. | INFINITY | 80 |

17. | FROM BONDAGE TO FREEDOM | 84 |

APPENDIX | 89 |