The possibility of being totaly 'clean' in a very dirty world may exist. The amount of people for whom that would actualy be practical must be miniscule at best.
From there it becomes a matter of degree?
No, I think it is a matter of how willing each individual is to give themselves an out. I think the people who came up with this final form of the definition of a vegan were giving people a lot of credit for being as ethical and conscience-driven as they were. It's human nature to project one's qualities onto others.
One would assume the idea of veganism, in its early days, would attract people with a certain set of ethics and an interest in living according to those ethics, who also possessed a keen sense of knowing when they weren't doing as much as they could have been doing, and an unwillingness to cop out on their principles or look for any excuse they could find to do what they wanted. Leaving "possible and practical" open to interpretation works for people who have a serious commitment to doing what they know is right.
So instead of having degrees of veganism, which really doesn't make sense to me, I'd rather leave it up to the person who wants to know why they can't eat honey, for instance, and call themselves vegan, to think about what the definition calls for, and be honest with themselves about why they really want the honey, and why they also want to think of themselves as vegan.
"Vegan" isn't the catch-all for every possible moral and ethical action, and it's not some lofty goal to be aspired to for achieving some sort of moral high ground. It's really just the bare minimum of common decency to others. In the years since the word was coined, it's gotten to be seen as some kind of status symbol for the socially conscious, in spite of the derision aimed at it by the majority. The more exposure it gets, the more "possible and practical" becomes the fall-back position to use when people tell us that since we live in houses and use roads, we are no more vegan than people who eat steak and wear fur.
