Robert Nozick, though, can't be dismissed on that ground.
To the entire left, Nozick, in effect, said: Your social justice comes at an unacceptable cost, namely, to my personal liberty. Most distressingly, to this end Nozick enlisted the humanist's most cherished belief: the inviolability of each human being as an end unto himself—what Nozick, drawing on Immanuel Kant, calls "the separateness of persons." For Nozick, the principle of the separateness of persons is close to sacred. It affirms, as he writes, "the underlying Kantian principle that individuals are ends and not merely means; they may not be sacrificed or used for the achieving of other ends without their consent. Individuals are inviolable."This is by way of taking his ideas seriously in order to criticize them. There's no surprise in learning that the author thinks that Nozick's ideas fail.
To the liberal humanist, Nozick is saying: You don't take your finest hero, Kant, seriously, because if you did, you would never sacrifice Wilt's autonomy to the social planner's designs. To the socialist, he is saying: You don't take your own finest hero, Marx, seriously, because if you did, you would never expropriate his surplus value (via taxation) as blithely as the capitalist. And to his own fellow Harvard professors, he is saying: You don't take your own finest hero—yourself—seriously, because if you did, why would you ever curtail the prerogative of a superstar?
What is surprising is that, eventually, Nozick himself came to think so.