The second part of Hart’s article makes an ambitious claim that many commonly accepted rights logically entail one natural right, the equal right to be free. What does “natural” mean? It means rights that are not derived from any social interaction. Rights derived from promises, by contrast, are derived from the interaction of making a promise.
In brief, Hart tries to show how the way we use two classes of rights makes sense only if we also believe in that natural right. There is no better way of explaining our invocation of those other rights.
“General” rights invoke the equal right to be free directly; that is the best explanation of what we mean when we assert that we have general rights. The two examples of “special” rights invoke the equal right to be free indirectly. For promises, the equal right to be free generates a hurdle that rights must cross to be justified: the obligation corresponding to the right has to be consistent with the equal right to be free. Mutual restrictions restore equal freedom when some people give up their freedom to produce goods that everyone can enjoy.
Michael suggested an intriguing twist on Hart’s treatment of special rights stemming from promises. Hart had said that the way promises work exposes our commitment to the equal right to be free: they only lose their freedom by giving it up voluntarily. Michael added that we can make another inference about rights, namely, that people have the right to make promises (and contracts, etc.). Nice point!
We had an extended discussion of mutual restrictions. At a minimum, this exposed several details that need to be worked out. Sydney thought that the whole thing would fall down eventually: everything plausible that is treated as mutual restricts could be assimilated to promises or contracts while everything else would be too implausible to take seriously. Hart’s purpose wasn’t so much to defend this as it was to note that it is commonly accepted and that it presupposes the equal right to be free.
I ended our session with a quick claim that Hart hadn’t actually shown that the right to be free has to be equal. For example, all that the point about promises shows is that people have some freedom and that they have the ability to give it up by making promises or contracts. It doesn’t follow that the freedom has to be equal. There can be promises in a feudal society, for instance.