Materialism — the belief that everything that happens is the result of the action of the basic laws of physics on the basic particles of physics — leads its adherents to some conclusions that most do not really believe but are obliged to assert.
For example, they often claim there is no real free will, that everything we do is determined by the laws of physics. But if they really believed this, why would they bother trying to convince the rest of us? Whether or not we will accept their conclusion is completely beyond our control. Certainly our behavior is influenced, maybe to a large degree, by our heredity and environment but no one would possibly conclude that he has no control over his own behavior if he were not forced to this conclusion by materialist philosophy.
Materialists are also forced—if they are consistent — to believe that there is no real good or evil, for how can some actions be “good” and others “evil,” if everything we do is beyond our control and determined by the laws of physics? While there is substantial disagreement among humans over the details of moral codes even atheists know in their hearts that there is a difference between good and evil. Have you ever known an atheist who did not appeal to morality to justify his actions, or to criticize those who disagree with him?
Materialists are also forced to believe that human brains are just advanced computing machines, and this leads to one of the most interesting inconsistencies of materialism. The current ID debate can be reduced to the question: is everything we see today simply the result of unintelligent causes or is an intelligent cause required to explain some things? (Even though the big bang theory has shown us that the laws of physics and the particles of physics are themselves the result of some cause beyond our universe, the debate is still over whether this first cause is intelligent or unintelligent. And even though quantum mechanics tells us that there is a “supernatural” component — forever beyond the ability of science to explain or predict — to all natural phenomena, the debate is still over whether or not this supernatural component is entirely random, i.e., unintelligent.)
But what does “intelligent” mean? Since humans are the only known intelligent beings in the universe, when we argue that a cause is intelligent, we can only mean “like humans.” But if you really believe that human intelligence, like everything else in the universe, is just matter in motion what difference does it make if a cause is like humans or like rocks? Both are just matter in motion. A consistent materialist would have to conclude that the ID debate is over a trivial distinction. But we all — including materialists — know that humans are not like rocks and so the debate is significant.