  An outline of Hart’s (1973) theory may be given as an illustration of the first view. According to Hart, someone (call him ‘X’) may be a legal right-holder primarily in one of two ways. First of all, X may have a bilateral permission to perform some action, i.e., X is permitted both to A and to not-A (together with there being some prohibitions on others interfering). Secondly, someone else may have a duty (e.g., to pay X £10) over which X has control, primarily by waiving or enforcing it. Since X has a choice in each case that explains why he is referred to as being a right-holder. One difficulty about this kind of theory is to explain our apparent reference to rights when there is no choice, eg when one is not only entitled to vote in elections, but also obliged by law to do so.