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Website to find Euclid’s Elements http://aleph0.clarku.edu/~djoyce/java/elements/elements.html Find the Table of Contents link Scroll down past the Introduction to the last line of text before “the credits.” Open the Table of Contents. Explore the site a bit Once in the Table of Contents, explore Introduction Using the Geometry Applet A quick trip through The Elements (Book I only) Look at Book I Return to the Table of Contents, scroll down just under the heading, Euclid’s Elements, and open Book I. Read through the Guide to Book I Return to the Book I page and open the propositions Read through the first five. Postulates Common Notions Postulate 1. To draw a straight line from any point to any point. Common notion 1. Things which equal the same thing also equal one another. Postulate 2 To produce a finite straight line continuously in a straight line. Common notion 2. If equals are added to equals, then the wholes are equal. Common notion 3. If equals are subtracted from equals, then the remainders are equal. Postulate 3. To describe a circle with any center and radius. Postulate 4. That all right angles equal one another. Common notion 4. Things which coincide with one another equal one another. Postulate 5. Given a line and a point not on Common notion 5. The whole is greater than the the line there exists exactly one line through the point and parallel to the given line. part.