The Wednesday panel discussion hosted by iDesign at UCI, a student-run organization, invited intelligent design advocates and evolutionists to thrash out the two theories in front of a student audience.
Around 150 students and members of the public gathered in the stadium-style seating of a lecture hall to watch PowerPoint presentations, enjoy free soda and engage in philosophical and scientific debate.
Advocates of intelligent design adopt an analogy first proposed by 18th century theologian William Paley. If he found a watch in a field, Paley said, he would assume a watchmaker had made it. In the same way, one might assume that the complexities in nature also were intelligently constructed.
For Bradley, a professor of evolutionary biology, the difference between the two theories stems from what he sees as a need in the theory of intelligent design to use a supernatural being to fill the gaps that science, so far, has not explained.
"Basically, as I understood their argument, when you get to a point where you are unable to explain something, you turn to intelligent design," Bradley said. "I was interested in mechanisms, so I was trying to get them to be more specific."
Nelson, a philosopher of biology, argued that leaning toward a supernatural designer was logically evidenced within science, not outside of it.
"There is evidence that the world was built by an intelligent mind like our own but vastly more complex," Nelson said after the panel discussion. "Intelligent design begins with biological evidence and asks, 'Could this kind of entity be formed incrementally through natural selection?' "
Nelson said evolutionists are unable to explain an explosion of life occurring between 543 million and 490 million years ago, when most of the major groups of animals first appeared in the fossil record.