Introduction

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Euclid's Elements form one of the most beautiful and influential works of science in the history of humankind. Its beauty lies in its logical development of geometry and other branches of mathematics. It has influenced all branches of science but none so much as mathematics and the exact sciences. The Elements have been studied 24 centuries in many languages starting, of course, in the original Greek, then in Arabic, Latin, and many modern languages.

I'm creating this version of Euclid's Elements for a couple of reasons. The main one is to rekindle an interest in the Elements, and the web is a great way to do that. Another reason is to show how Java applets can be used to illustrate geometry. That also helps to bring the Elements alive.

The text of all 13 Books is complete, and all of the figures are illustrated using the Geometry Applet, even those in the last three books on solid geometry that are three-dimensional. I still have a lot to write in the guide sections and that will keep me busy for quite a while.

This edition of Euclid's Elements uses a Java applet called the Geometry Applet to illustrate the diagrams. If you enable Java on your browser, then you'll be able to dynamically change the diagrams. In order to see how, please read Using the Geometry Applet before moving on to the Table of Contents.

I often hear that geometry is no longer taught well here in the United States high schools. (I also understand that it is not taught at all in some high schools.) This is a major problem because deductive logic is learned almost exclusively in geometry. Without understanding logic, students will have difficulty in their daily lives, and difficulty in college, if they go on to college.

Modern mathematics and science use deductive logic as a primary tool of understanding. In mathematics, especially, nothing is considered to be known until it is proved.

One contributing factor, perhaps the major contributing factor, to the downfall of geometry education in the United States is the way it is presented in text books. If the logic is not presented in text books, it is very hard for the teacher to insert it in class.

A recent text book, Prentice-Hall's Geometry: tools for a changing world shows how poor geometry education is today. For details, see my review of the book.

For a broader criticism of mathematics education in the United States, see the site Mathematically Correct.

These pages are located at http://aleph0.clarku.edu/~djoyce/java/elements/elements.html.