The discussion revolves around two key ideas about the nature of law and power, related to the concept that legislation is the only source of law. The first idea is that a legislator's power must be unlimited, as any limitation would require an even higher authority. The second idea posits that anything established by this supreme legislator is law solely based on their will. This perspective transforms law from being a barrier against power into a tool for exercising it.
Legal positivism argues that there are no real limits on a legislator's authority, but this view is flawed because it ignores the source of that authority, which lies in public opinion. A legislator's power is based on a shared understanding of what rules must generally include to be seen as legitimate. Therefore, legislators can only effectively use their power if they satisfy public expectations regarding the qualities of laws.
This principle applies to all authorities, including dictatorships, which depend on public support to remain in power. Without this backing, even the strongest leaders can fail. Ultimately, public opinion sets limits on all legislatures, dictating the rules they can enact. Such constraints can exist without needing additional governing bodies, arising instead from societal beliefs about what constitutes lawful conduct.