Final answer:
The legal theory advocating for the existence of laws that occur across all cultures is known as legal universalism, which supports the idea that fundamental legal principles are globally applicable, and contrasts with normative ethical relativism that upholds culturally specific moral and legal standards.
Step-by-step explanation:
The legal theory that posits the existence of laws that occur across all cultures is known as legal universalism. This theory suggests that there are fundamental legal principles that are universally applicable, regardless of cultural differences. Legal universalism parallels the concept of universal laws in nature, which apply uniformly across the universe. It is the philosophical opposite of theories like normative ethical relativism, which argue that moral and legal rules are culturally specific and can vary from one society to another.
Legal universalism would facilitate international relations, commerce, and a shared understanding of human rights, suggesting that basic legal concepts should be consistent across borders. In contrast, normative ethical relativism recognizes the diversity of moral rules and customs, which vary significantly across cultures, leading to the view that no single moral framework should be applied universally.
It is noteworthy that the existence of universal laws enables us to comprehend and establish predictability in various dimensions such as in astronomy, governance, and societal interactions, similarly to how legal universalism would attempt to provide a stable framework for cross-cultural interactions and understanding within the realm of law.