Really? The man you’re addressing is a great libertarian economist, and one of the first LRC writers I read when I began reading LRC.
I’m pretty sure that Mr. Callahan does not consider himself a libertarian, at least he doesn’t seem to agree with most of the theory. I responded to his blog post on homesteading here. As far as I know he doesn’t “have a coherent theory of morality or justice”, just like most who take swipes at libertarianism. I’m not sure what he is even responding to here.
I didn’t read this thread but, given the person who is faced with this choice isn’t responsible for hte people being on the tracks, I think the right answer is to do nothing in order to avoid culpability. Still, I think that a person in a hypothetical free society might be able to switch from the track with 5 people to the one with 1, having some knowledge of how justice firms have codified law, without much fear of prosecution. While we are typically concerned with theoretical, praxeological law, jurisprudence, or law in action, is a separate discipline. What I’ve termed the via negativa of libertarian justice is that a judge might simply refuse to act on a crime.
An example I’ve used along with this is a hypothetical person who trespasses while fleeing a mudslide. Since it’s somewhat time consuming to figure out what an appropriate punishment for trespass is, we’d typically see monetary fines, but either way, a judge who stands to gain very little from doling out this fine might stand to lose a lot more from the publicity of being the cruel judge who punishes the poor guy who almost got smothered in a landslide. The case in this pathological hypothetical is more severe since 1 person will die, but I couldn’t see many judges handling it in any other way.