Philosophical naturalists believe that the physical universe is all that exists. As a result, they reject the idea of God, and the idea that morality - our sense of right and wrong, and what ought to be - comes from God. Can morality be explained in purely physical terms?
Scientism is a relatively new word. It describes an exaggerated belief in the ability of science alone to explain the world around us. Our scientific understanding of nature keeps changing, but philosopher J.P. Moreland suggests that our moral sense is more reliable than science.