We assumed ethics needed the seal of certainty, else it was non-rational. And certainty was to be produced by a deductive model: the correct actions were derivable from classical first principles or a hierarchically ranked pantheon of principles. This model, though, is bankrupt.
I suggest we think of ethics as analogous to language usage. There are no univocal rules of grammar and style which uniquely determine the best sentence for a particular situation. Nor is language usage universalizable. Although a sentence or phrase is warranted in one case, it does not mean it is automatically appropriate in like circumstances. Nonetheless, language usage is not subjective.
This should not surprise us in the least. All intellectual pursuits are relativistic in just these senses. Political science, psychology, chemistry, and physics are not certain, but they are not subjective either. As I see it, ethical inquiry proceed like this: we are taught moral principles by parents, teachers, and society at large. As we grow older we become exposed to competing views. These may lead us to reevaluate presently held beliefs. Or we may find ourselves inexplicably making certain valuations, possibly because of inherited altruistic tendencies. We may "learn the hard way" that some actions generate unacceptable consequences. Or we may reflect upon our own and others’ "theories" or patterns of behavior and decide they are inconsistent. The resulting views are "tested"; we act as we think we should and evaluate the consequences of those actions on ourselves and on others. We thereby correct our mistakes in light of the test of time.
Of course people make different moral judgments; of course we cannot resolve these differences by using some algorithm which is itself beyond judgement. We have no vantage point outside human experience where we can judge right and wrong, good and bad. But then we don’t have a vantage point from where we can be philosophical relativists either.
We are left within the real world, trying to cope with ourselves, with each other, with the world, and with our own fallibility. We do not have all the moral answers; nor do we have an algorithm to discern those answers. Neither do we possess an algorithm for determining correct language usage but that does not make us throw up our hands in despair because we can no longer communicate.
If we understand ethics in this way, we can see, I think, the real value of ethical theory. Some people, talk as if ethical theories give us moral prescriptions. They think we should apply ethical principles as we. would a poultice: after diagnosing the ailment, we apply the appropriate dressing. But that is a mistake. No theory provides a set of abstract solutions to apply straightforwardly. Ethical theories are important not because they solve all moral dilemmas but because they help us notice salient features of moral problems and help us understand those problems in context.
It is implied in the passage that a relativistic view of ethnics（）
A. can only be acquired after real life lessons
B. often generate unacceptable consequences
C. is more mature and rational
D. is too abstract to be of any practical value