“You must become the change you wish to see in the world”. So said Ghandi, and as activist admonitions go, it is sage advice. There is nothing like leading by example. The image of the crusader walking the walk is worth a thousand posturing speeches. However, it is important to note that this is, at its core, a pragmatic argument*. It is not one of moral imperative, or logical necessity. Thus, this argument by Bill Dembski:
"Is it possible to copyright a song that disavows possessions (copyright being a form of possession)? Once Ono realizes the self-referential incoherence of her suit, I trust she’ll drop it."
…has no more validity than the arguments made by those who would dismiss global warming because of perceived failings in Al Gore’s personal life. There is no moral or logical argument that says one must behave now as if the rules were the way one wants them to be. If I am a basketball coach, and I believe the 3-point shot ought to be abolished, that puts no onus on me to not accept 3-points for those shots. Likewise, if Yoko Ono thinks society would be a lot better off if no one concerned themselves with possessions, that places no onus on her to have no concern for her possessions now. Such an argument ignores the prisoners' dilemma, and makes the reverse mistake of that at the root of the tragedy of the commons.
That is, an action that is advantageous for a group to do, might be highly disadvantageous for individuals to do, especially if others do not take that action. Disarmament is an extreme example. Humanity might be better off if we all disarm, but America is not going to be better off if only we disarm. Likewise, one might argue mankind would be better off living in communes rather than capitalist societies, while still recognizing the impracticality of attempting to live as if one lived on a commune while living in a capitalist society. This is essentially what Dembski is arguing Yoko must do to be consistent with her husband's song.
And lest the world forget, the ultimate in self-referential incoherence was the Expelled crew, who claim they are censored and expelled unfairly, did everything they could to censor criticism, and expelled a thanked star of their film from attending a free screening of it. I owe you all some irony-meters.
* I am concerning myself with this argument in and of itself. I am therefore assuming that one does not add on any other obligations, which then would, obviously, negate my assumption. For example, if you make your normative argument based on morals, then obviously that same argument would apply to you.