Why should it be controversial to claim that in the past couple of centuries materialism and other naturalistic philosophies—including naturalistic versions of Darwinism—have eroded Christian moral standards that dominated Western culture for centuries?  Is there not biblical sanction for the view that atheism and agnosticism—indeed any denial of God's participation in human affairs—leads to moral depravity?  Paul asserts in Romans 1 that those who reject the knowledge of God will become ensnared in "vile passions," and because of their "debased mind" will be "filled with all unrighteousness," including sexual perversion.  Wrong ideas about metaphysics do indeed have consequences for morality (see also Ps. 14:1).

Yes, but … when we compare the moral character of theists with materialists and agnostics, we face an obvious conundrum.  Many theists' behavior is deplorable, as atheists and agnostics regularly remind us, invoking the Crusades and Inquisition to dismiss Christianity.  Any churchgoer can add contemporary examples (not to mention the outcome of a little self-examination). On the other hand, some materialists seem exemplary in their conduct, at least in their treatment of other people.  So in what sense, then, do naturalistic philosophies undermine morality?

Many leading materialist thinkers in the past two centuries have acknowledged that their philosophy destroys the foundation for Christian ethics, and quite a few have forthrightly attacked Christian morality as outmoded.  The philosopher Daniel Dennett, for example, describes Darwinism as a universal acid, dissolving all our traditional concepts, such as religion and morality (but somehow Dennett's materialist metaphysics is impervious to the "universal" acid). E. ...