2. Relativism. The second claim is that everything is relative (meaning, morality, human worth, etc.). Critical thought shows that this is immediately contradictory because the statement that everything is relative must be a relative statement and therefore not always true, or it is an absolute truth and therefore disproves itself. Within the idea that everything is relative, there are three domains that I think are important to understand and that people do not treat as though they are relative, no matter how committed they are to relativism. When examining their presuppositions, you will always find an absolute which the rest of their views rest upon.
A. Truth & Reason. Without God, we can never even claim to know the truth about anything. For all we know, our whole experience of life could be nothing more than an illusory byproduct of a chemical reaction. It also might be possible that we are living in the Matrix or some other fantasy realm. Reason also becomes suspect because we cannot assume an intelligent designed that created ordered, rational, coherent universe. If human reason is nothing than the product of chance, with no intelligence behind its creation, how can it be trusted to lead to right answers? Without presupposing God, we cannot trust reason and there is no truth for which we use reason to uncover.
Additionally, why would truth matter? If someone claims to be an atheist because it is true that God does not exist (which isn't try, but atheists think it is), then the questions becomes why does truth matter? If truth is relative, then couldn't it be relatively true that there are things that are more important than truth? For instance, numerous studies show that religious people are generally happier and more fulfilled in life. Couldn't that be considered more important than truth?
B. Meaning. If meaning is relative then everything is essentially meaningless. Our words, thoughts, actions, beliefs, and the whole of the universe becomes meaningless. A person's strongly held atheistic views become meaningless as does their view that science or evolution is true. Even if it's true, it doesn't matter because there is no meaning in truth. There is no more meaning to a person's life than there is for the life of a monkey, dog, amoeba, or even a rock. From a relativistic perspective, meaning is just an illusion.
C. Morality. Evolution offers an acceptable explanation about how we evolved a moral framework, but it doesn't tell us if moral decisions are right or wrong. From a relativist perspective of morality, the terms right and wrong have no meaning. However, relativists still try to claim that their views of morality are somehow better, but they have no absolute standard to use to determine if their views are better. For instance, we know that 2+2=4. That is the standard we have for right and wrong, better or worse. If I say 2+2=3, I am still wrong, but I am close. On the other hand, if someone says that 2+2=246, then they are way off. Being wrong but close may be much better in an engineering mistake than if someone was way off. From a relativistic perspective 3 is just as good of an answer as 246 because there is no standard of what is right, but somewhat hypocritically, they try to claim that their individual answer is better than that of Christians, government, prior historical cultures, and even other atheists. In an attempt to have a consistent view of morality, they often refrain from claiming to be right, but instead they use other adjectives such as better, complex, civilized, cultured, robust, wise, or helpful, etc. to try to advance their particular moral framework. Unfortunately, these adjectives still assume some sort of absilute standard of right and wrong. Why is complex better than simple if there is no right answer? Something cannot be better if there is no correct answer for it to be closer to.
Practically speaking, if morals are relative, then we can take any position on moral choices, and then use any reason to justify it. This is why atheist led governments (Stalin, Mao Zedong, Pol Pot, Mussolini, Kim Jong Ill, Castro, and many more) have been responsible for more pain, suffering, death, and destruction than all other governments throughout history. One potential explanation for this is that it cannot be assumed that people have inherent self-worth, therefore, people only have worth or value if they earn it. Atheists may want to deny this, but there is no logical reason for their position. If they claim humans have any kind of intrinsic value, it is merely because underlying that claim is their emotionally driven opinion. It is not a decision driven by reason.
Many atheists are good people by the worlds standards and often highly intelligent. Unfortunately, many of them are unwilling to follow their beliefs to their logical conclusions or unwilling to critically examine their presuppositions (or even admit that they have presuppositions). We need to recognize and use our emotions, but our emotional reactions should stem from a foundation of reason. Atheists are forced into the opposite position where their emotions serve as the foundation for their reasoning.