David Post at Volokh has a good example of a view of whether someone is “free” to do something that will strike most libertarians (including myself) as nonsensical. Something like this is believed by most proponents of “positive rights”. The classical liberals likely based some of their understanding on a belief in free-will. Unlike Bryan Caplan, I find that notion incoherent although I still like his “gun to the head test” for determining limited potential vs volition. Part of my issue with that conception of freedom is that it “proves too much”. If every situation is unfree, there is no use for the concept of freedom as a contrast. I think Matthew Mueller may have been inching toward something like that (and Jeffrey Friedman may have already crossed that line long ago) before he gave up blogging. Economics tells us that we face trade-offs for every action we take. In that sense we are not “free” to take actions with no tradeoffs. What kind of tradeoff is severe enough to be deemed important seems rather subjective. The gun test handles issues of sheer physical impossibility, but there’s room to expand that a bit, especially if we extend the time-frame from the momentary execution of an act to incorporate possible reactions. I may be free to steal something of yours, but if it will reliably taken back from me we can exclude more than momentary possession of it (presumably the point of grabbing it in the first place) from my choice set. Am I not free to possess something I must pay for? That I would see as just another example of the usual tradeoffs. There is a set bar I have to pass. That is distinct from a situation in which there are other agents aware of my actions dedicated to stopping them and willing to set an arbitrarily high cost for my taking such actions. It does seem to me that there is something psychologically distinct from fees and fines, though it also seems conceivable that there is something about the latter that distinguishes it from the former (perhaps an effect that shows up after repeated iterations showing that you regard the fine as simply a fee).