Answer
Pragmatic ethics is one of the three main schools under the umbrella of ethical relativism. Ethical relativism teaches that right and wrong, good and bad, are relative to the situation, circumstances, or personal conviction. Cultural relativism is another school of relativism, but it is less an ethical framework than a tool for anthropologists to use to remind themselves that other cultures have different social mores. Moral relativism teaches that morality is merely the following of any ethical framework—one is as good as another. Pragmatic ethics takes a more aggressive approach, insisting that mankind is responsible for determining the best ethical system possible, which will be refined as new discoveries are made.
Pragmatic ethics is the philosophy of ethics most championed by atheists and evolutionists. It combines the worldview of materialism (the supernatural does not exist) with the methodology of science in an attempt to develop a code of behavior for mankind. "Pragmatic" refers to the belief that we should use what works and alter or discard what doesn’t. Pragmatic ethics does hold that absolute/universal truth exists. But it also teaches that the imperfect human intellect will never recognize truth; all we can do is endeavor to get as close as possible. Practically speaking, then, pragmatic ethics is relativistic.
PRAGMATIC ETHICS - THE WORLDVIEW
The worldview of atheistic materialism directly relates to the theory of pragmatic relativism. If everything in the universe is physical and the supernatural does not exist, then the spiritual has no effect on the physical world we experience. This means no God, but it also means no human soul, no afterlife, no thought, no feeling, and no consciousness. If we appear to feel or think something, it is merely a physiological reaction to stimuli.
The philosophical application of this is that humanity’s value, identity, and character have no innate worth and are not imbued by a Creator. We are simply physical beings interacting with the world. We are defined by the effect our actions have on other physical entities. Ethics takes on a great importance, then, since ethics is the standard by which we (should) interact with the world around us.
PRAGMATIC ETHICS - THE METHODOLOGY
Although it isn’t widely known, one of the key beliefs of most scientists is fallibilism. Fallibilism is the stance that mankind is incapable of knowing when we have come upon the truth. The truth may exist, and we may even believe the truth, but we will never know for sure when or if we do. Yet it is still our duty to seek the truth. We do this is by guessing (hypothesizing), experimenting, and then seeing if our guess was correct.
Fallibilism applies to ethics, too. Truth about human behavior may exist—an absolute standard we are meant to follow. But we will never know if we have discovered that truth. And so our duty is to observe and contemplate which actions lead to the best results for humanity. With continued effort and experimentation, we might come closer to knowing how to live.
PRAGMATIC ETHICS - THE SHORTFALLS
Pragmatic relativism doesn’t work for several reasons. First, it purports to strive toward truth while completely rejecting God. God is truth. He is the I AM—the essence of existence. Of course, mankind has done this since the Garden of Eden—searched for truth outside of God. The tragedy of pragmatic relativism is that it acknowledges many biblical truths (e.g., truth does exist, finite humans cannot fully understand truth, and mankind is responsible to live according to a truth we don’t know) while completely ignoring the fact that Truth came down and walked among us (John 1:1; 14:6). It’s like a lizard lying in a desert, willing to accept that light and heat are realities and knowing that his little lizard brain will never fully understand them, but refusing to believe that there is a sun.
Pragmatism gets some things right, like the fact that ethics and right behavior are directly related to truth. Psalm 15:2 speaks of the man who "walks with integrity, and works righteousness, and speaks truth in his heart." Scripture also agrees that mankind will never discover truth with our limited intellect (called a “darkened understanding” in Ephesians 4:18). John 14:16-17 teaches that truth only comes from God: "I will ask the Father, and He will give you another Helper, that He may be with you forever; that is the Spirit of truth, whom the world cannot receive, because it does not see Him or know Him, but you know Him because He abides with you and will be in you." And John 15:26 says we cannot understand the truth about God incarnate without the leading of the Spirit.
But the Bible differs from pragmatic relativism in that God teaches that mankind can know truth—with help. Absolute truth exists, and it is knowable. Psalm 51:6 says, "Behold, You desire truth in the innermost being, and in the hidden part You will make me know wisdom." Proverbs 3:3 agrees: "Do not let kindness and truth leave you; bind them around your neck, write them on the tablet of your heart." In addition, we are to worship in truth (John 4:24), discern truthfulness in our leaders (Matthew 7:15-20), and be characterized by truth (John 17:17; Ephesians 6:14).
Romans 1:18-32 explains why pragmatists refuse to acknowledge God’s truth. "For even though they knew God, they did not honor Him as God or give thanks, but they became futile in their speculations, and their foolish heart was darkened…For they exchanged the truth of God for a lie, and worshiped and served the creature rather than the Creator, who is blessed forever. Amen" (vs. 21, 25). When men refuse the truth of God, whether that truth is a warning that forbidden fruit will bring certain death or God’s very existence, they reject God’s sovereignty over them. With God’s guidance flouted, something must take its place—"the creature" of verse 25. In the case of pragmatic relativists, that "creature" is mankind—the base, physical, material part of man. Not even the heart or soul of man, because that would be too close to God, but arms and legs and neural synapses. The search for truth is futile in their case; 2 Timothy 3:2, 7 says that people who seek truth apart from God are "lovers of self …always learning and never able to come to the knowledge of the truth."