I think the crux of this is that he, in his subjective estimation, believes that the NAP violates itself based upon each person's subjective definition of what aggression is, rather than based upon how the NAP itself defines aggression. We know absolutely how the NAP defines aggression, even if he may define it differently in his subjective view. Therefore we can say that his subjective view is objectively wrong, because words have meaning and the NAP defines its own terms. Or at least we've all come together to agree subjectively that words have certain standardized meanings, and that is the measure by which we interpret words; specifically, the words of the NAP whereby aggression is defined absolutely. He's welcome to interpret them differently if he'd like, but he'll find that he is no longer able to communicate efficiently with us.
In a phrase: We hold these truths to be self-evident.
Now the fun part is determining just how consistent a subjectivist he really is. Because if he's really consistent, the most he can say is that he thinks we're probably wrong; saying we're definitely wrong would be an objective statement, implying that we have the ability to discern the nature of reality.
objectivity does not exist. http://en.wikipedia.org/wiki/Brain_in_a_vatIn a phrase: We hold these truths to be self-evident.
Now the fun part is determining just how consistent a subjectivist he really is. Because if he's really consistent, the most he can say is that he thinks we're probably wrong; saying we're definitely wrong would be an objective statement, implying that we have the ability to discern the nature of reality.
