Dr. John McCoy disucsses how people in previous civilizations were able to use conics for practical uses before the development of more modern mathematical equations. Dr. McCoy is a retired computer science professor who spent 33 years at Sam Houston State in Huntsville, Texas. He visited several classes on March 28, including the Algebra II classes taught by Denise Gregory, his daugther. "To me, this is just play. I don't get paid to think anymore," he said. Dr. McCoy said he began studying conics a few years ago when Gregory poised a question about parabolas to him.