Armstrong contended that belief in the existence of God is not necessary for universal morality to exist. D'Souza, on the other hand, asserted that religion is both fundamental to, and responsible for, morality. While the tone of the discussion was friendly, the debate became contentious at points, such as when D'Souza said atheism is responsible for the worst atrocities of the twentieth century.
"I estimate that the crimes of all the religions of the world put together are less than one percent of the crimes of a handful of dictators in one half century," D'Souza said.
Joseph Stalin, Mao Zedong, Pol Pot and other dictators were motivated by atheist ideologies, he said.
Sinnott-Armstrong disputed D'Souza's attempt to blame atheism for these atrocities, arguing that these dictators were fanatics and ideologues hijacking the atheist world view to accomplish their own ends.
D'Souza said he sees Christianity as the foundation of Western civilization. Abolitionism, civil rights, individualism, free speech and other values are all principals rooted in the Christian tradition, D'Souza said.
Democracy and the abolition of slavery both originate in the idea that all men are equal in the eyes of God, D'Souza added.
He also mocked the idea of a materialist universe and Darwinian evolution as the sources of morality.
"If all we are is primates, then even our morality must be seen as a cunning device to pass our genes on to the next generation," he said.
Followers of this world view would see a mother saving her children from a burning car as merely protecting her genes, he added.
Sinnott-Armstrong directly addressed the question of whether God exists, arguing that the Christian God is superfluous to the question of morality and inconsistent with the evils of the world.
"An all-good God would want to stop that evil, an all-powerful God could stop that evil," he said, referring to deadly forces in the world that are beyond mankind's control.
Immoral actions are those that cause harm, he said, and a concept of morality based on preventing harm can exist independent of any divine or supernatural force.
"All we can do is be good to each other in this world, where we have to live our lives after all," he said.
Sinnott-Armstrong's concept of morality is limited because many atheists use the idea of a godless world as a license to pursue whatever actions they see fit, D'Souza said.
"The way to pull out from the shadow of moral judgment is to abolish the judge," he said.
Supporters of Sinnott-Armstrong handed a list of Bible verses to audience members as they entered Alumni Hall. Sinnott-Armstrong used these verses, which come primarily from the Old Testament and condone actions such as slavery, mass-murder and gender inequality, to say that the Bible supports immorality.
"The rabbis really have some explaining to do, don't they?" D'Souza said in response.
The Christian religion sees the Old Testament as superseded by the New Testament, he said.
D'Souza recalled the Spanish missionaries who originally converted his Indian ancestors to Christianity. While he noted that these missionaries came with "a bible in one hand and a sword in the other," he said low-caste Hindus flocked to Christianity because its message of universal brotherhood allowed them to escape the oppressive caste system.
"The Indians recognized that something new had been brought to the world," he said.
One questioner later denounced this statement, saying that D'Souza was misrepresenting the Hindu religion. The questioner stated that the great Indian epics include lower-caste men and women as heroes. D'Souza responded by saying that he was speaking of his own family's experience and was not condemning Hinduism as a whole.
D'Souza has already debated Christianity and atheism five or six times this year, he said, and plans to attend two more debates later this week.
"A lot of Christian apologists, or defenders, stay in the church world," he said, "I wanted to take this argument to the students."
