Is living a moral life impossible? I’m inclined to say yes, because in many instances, rational deliberation about morality will lead to conclusions that subvert common sense and demands one to do things that one would not usually do.
The first example that comes to mind is Peter Singer’s argument about the moral obligation to donate to charities that help people far away geographically. People have this intuition that they ought to do something if it saves lives at no significant cost to themselves. Yet a lot of people do not donate to charities like OXFAM or UNICEF, which pose no significant cost to them, but can save people far away.
This is only one easy example; there are many other demands of morality which require people to do things that they do not want to do.
Traditionally philosophers have dealt with the demands of morality in roughly two ways. First, they either try to modify the premises such that a different, less demanding conclusion is raised; or, more rarely, they bite the bullet like Peter Singer does.
I personally find too much use of the first method to be disingenuous. Ethical philosophy should not be entirely about reconciling common sense intuition with systematic thinking; ethical philosophy should be the enterprise to find out what the right thing is. There is no logical necessity that states that these conclusions must not demand of us what we would not want to do.
That we do not want to follow the conclusions of moral deliberation does not mean that the conclusions are wrong; it may merely mean that we are incapable of living a moral life.
I am inclined to go with the latter, because through experience, I’ve observed that people rarely do the right thing, even if they really know what the right thing is. That we experience real moral dilemmas does not mean that there are two difficult choices; it could just mean that we are hesitant to choose the path that is difficult, but ultimately correct.
This, however, is not a reason to not try to act morally. The impossibility of living a moral life does not justify one’s not even trying to act morally. In the end, the ethical thing, in fact, the only ethical thing, that we can possibly do is to try.
But we will fail, almost inevitably.