Friedrich Nietzsche declared God dead at the hands of science more than 100 years ago.
In a lecture entitled "Why God Won't Go Away: Brain Science and the Biology of Belief," Andrew Newberg argued that the concept of God remains very alive today, as a result of normal physiological processes.
"Religion seems to be some pretty tenacious stuff," said Newberg, a professor in the Department of Radiology at the Hospital of the University of Pennsylvania. "Our mind moves us to be spiritual or religious."
Armed with images that detail the brain's activity during meditation and prayer, Newberg tried to show a parallel between spiritual activity and physiological changes.
At the beginning of meditation, Tibetan Buddhist monks in Newberg's lab focused on a visual image.
According to Newberg, this intense concentration causes activity in part of the frontal lobe, which he described as the "attention activation area."
The brain then begins to filter out other sensory information to help with concentration. The result is a decrease in activity of the brain's "orientation activation area" -- an area which "helps to create a three-dimensional picture of who we are and how we relate to the world," Newberg said.
Inhibition of this area could lead to a decreased awareness of self. Newberg said this is consistent with the monks' belief that their identity was becoming one with the visual image they focused on during meditation.
The correlation between measurable physiological changes and spiritual practices helps explain why religion continues to affect people, he said.
However, Newberg cautioned that being able to track physical changes that occur alongside religious experiences does not detract from their validity.
"Just because we can stimulate it doesn't mean it's not something real," he said.
Newberg explained that smelling an apple pie causes measurable changes in the brain, but this does not mean the pie is imagined.
Instead, he argued that humans should re-evaluate the concept of reality.
"All of our experience of reality... is ultimately processed through the brain," Newberg said.
Since all information is filtered by the brain, humans can at best get a secondhand picture of the world.
"Whatever we seem to hold and believe is true... is probably a lot more complex" than we can understand, Newberg said.
In this sense, he suggested that religious experiences and everyday sensory perception could both be equally real because both represent activity in the brain.
Because of this, Newberg said it is important to look to religion, as well as science, to understand the human experience.
After all, based on physiological evidence, "the concepts of God and religion are likely to be with us for some time," Newberg said.
Newberg's lecture was the third of this year's Penn Humanities Forum, which is focusing on the topic of belief.
Humanities Forum Co-Director Peter Stallybrass called the turnout -- 275 to 300 people -- "a mob scene."
Music Professor Carol Muller, the topic director for the year, was also impressed.
The forum, she said, is about dislodging comfort zones.
"Often you believe what you do is true, but it is just belief," she said.
