Sample Informative Speech Preparation Outline Topic: Pi General Purpose: to inform Specific Purpose: to inform my audience about the nature of pi. Thesis/Central Idea: I plan to inform you what pi is, the history of pi and how pi has created obsessions in people’s lives. Introduction:
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3.1415926558979323862643832795 (catch attention) A. Most of you know the name of the number I just recited. B. It is found in rainbows, pupils p upils of eyes, sound waves, ripples in the water and DNA. C. It is a ratio that nature and music understand but that the mind canno t comprehend. D. This number has sparked curiosity over the past 4000 years. E. I am talking about pi – not the dessert, but the circle circle ratio. (reveals topic) I will try to present pi as the fascinating fascinating topic I think it is to a class of speech majors who wonder if they can survive a speech about math. A. I have researched this topic, finding information not only technical and historical, but also fanatical. (establish credibility) B. My own interest came about when I was challenged to memorize more digits than a friend of mine. I plan to inform you what pi is, the history of pi and how pi has created obsessions in people’s lives. (preview of main points)
Body:
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Even if you don’t know kn ow what it represents, pi is a number that almost everyone is familiar with. A. When you divide the circumference of a circle by its diameter, the result will always equal pi. 1. No matter the size of the circle, this division results in what called the circle ratio. 2. Although we refer to pi as 3.14 or 22/7, it is actually an irrational number, meaning that it cannot be represented as a fraction. 3. The number pi is never ending – or is it? 4. For ages, mathematicians have puzzled, and have been almost ashamed, that it is so difficult to find another value as simple the circle ratio. B. Pi is more than just the circle ratio. 1. According to David Blatner, who wrote “The Joy of Pi,” this value can be found in all fields of math and science, architecture, the arts and even in the Bible. (Blatner 44)
2. The world record for calculating pi to the greatest number of decimal places is 206 billion decimal places, calculated by Dr. Kanada at the University of Tokyo. Transition: Although 206 billion digits have been calculated thus far, there was a time in antiquity when there was uncertainty of the second decimal place.
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Woven among pi’s infinite digits is a rich history, ranging from the great thinkers of ancient cultures to the supercomputers of the twentieth century. A. Four thousand years ago, there was no decimal system, compass, paper or pencil, yet people still found ways to calculate pi. 1. The Egyptians used a stake, a rope and the sand to approximate pi as a little greater than 3. 2. The Greeks, Babylonians, Israelites, Chinese and Mesopotamians also studied the circle ratio, yet none of them were certain of the third decimal place. B. Whether pi is an infinite number remained a mystery until the sixteenth century. 1. Petr Beckman, a former professor of engineering at Colorado University, likes to call this period the age of digit hunters, with each generation popping out more digits than the next. (Beckman 13) 2. Keep in mind that at this point the electronic had not yet been invented. 3. Famous mathematicians of the time continued to break records for calculating pi. C. In the twentieth century, the invention of the computer allowed mathematicians to calculate pi to 16,000 digits, confirming that pi is infinite and totally random.
Transition: What is the fascination with pi that has caused people to be both fascinated and obsessed?
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Blatner states, “People have calculated, memorized, philosophized and expounded on pi more than any other number in history.” (Blatner 47) A. The Chudnovsky brothers, Gregory and David, were both mathematicians from Russia who moved to New York to entertain their obsession with pi. 1. In their own apartment, they built a supercomputer from scrap materials. 2. With this computer they were able to calculate more digits and to study its use in various formulas. B. Other people try to memorize pi. 1. Some do it for sport or to be silly, but others are more serious. 2. Blatner states that in 1995, Hiroyuko Goto spent over nine hours reciting 42,000 digits of pi from memory, far exceeding the world record.
a. This was a rare case, but there are methods of memorization for the average memory. b. Some people remember pi through poems, clever mnemonics and songs. c. Some simply memorize the digits in groups of fours, which the method I’ve found easiest. C. So many people are obsessed with pi that the number is celebrated on Pi Day every March 14 or 3/14. 1. The Web site Ridiculously Enhanced Pi Page suggests that you gather with friends at 1:59 pm to celebrate. (http://www.exploratorium.edu/pi/pi98/) 2. At this time, eat pie and share personal stories about pi. Summary Transition: So ends my analysis of people’s obsessions, but my earlier question was not fully answered. Conclusion:
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No one knows for sure why pi has caused such a craze, why several books, movies and Web pages have been devoted to this subject. (brings speech to an end) A. What inspired the Chudnovsky brothers to devoted their lives to the search for pi? B. What inspired me to write a speech on a silly number? C. The answer lies in the mystery of pi: People explore pi because it is an adventure to do so. Remember that pi not only the circle ratio, not the biggest influence on math over history, but also a number that has a great affect on people and an influence on everything we do. (reinforces thesis and summarizes main points) William Schaaf in “The Nature and History of Pi,” concludes that “probably no symbol in mathematics has evoked as much mystery, romanticism, misconception and human interest as the number pi.” (Schaaf 78) Works Cited
Beckmann, Petr. A History of Pi. New York: St Martin’s Press, 1971. Blatner, David. The Joy of Pi. New York: Walker and Company, 1997. Blatner, David. “Pi Facts and Figures.” The Joy of Pi. Accessed 20 September 2000. http://joyofpi.com/. Schaff William. “The Nature and History of Pi.” The Joy of Pi. Accessed 20 September 2000. http://www.joyofpi.com/schaaf .
Witcome, Chris. “Notes on Pi.” Earth Mysteries. Sweet Briar College. Accessed 23 September 2000. http://witcombe.sbc.edu/earthmysteries/EMPi.html. Ridiculously Enhanced Pi Page. Posted 1998. The Exploratorium. Accessed 23 September 2000. http://www.exploratorium.edu/pi/pi98/
