In response to Mary...

In response to Mary's question: If we strive so much to be virtuous and good etc., and these are notorious subjects of ambiguity, are they something that is unknowable? Or are they just something that we dont know yet?
I think that determining an ultimately "good" lifestyle falls under the unknowable category because I believe that goodness is completely subjective. What one person may have no qualms about doing or thinking, another might find completely inappropriate. I believe that the human consciousness created the concept of good and evil in the first place, and therefore arbitrarily chooses what is "good" and what is "evil" according to the beliefs we as a society have created. One might bring up an argument that our consciences tell us what is good or evil or virtuous or not. However, I believe that the human conscience does not exist in and of itself, but is rather constructed over time through the beliefs of a society as a whole and the private thoughts of the individual. We cannot know the intrinsic goodness or evilness of an action; we may only know what society deems "good" or "evil."
Now, I dont mean to sound like some depraved degenerate, because I do believe in our accepted standards of what is right and wrong, what is good or evil. I only mean to argue that, though these beliefs make sense to us and follow the general rules of justice and fairness, it does not mean that they are in some way intrinsically good unto themselves.
Q: How do you personally decide what is good or evil, right or wrong?