Antinomy refers to a contradiction between two principles or laws that are both valid but cannot coexist. This concept often arises in philosophy, particularly in the works of Immanuel Kant, who explored antinomies in his critique of pure reason. In essence, an antinomy presents a situation where two opposing arguments or truths exist, leading to a paradox. In logic and mathematics, antinomies can highlight inconsistencies within a system. For example, the Russell's Paradox illustrates an antinomy in set theory, where a set cannot contain itself without leading to a contradiction. Understanding antinomies helps clarify complex issues in reasoning and the limits of knowledge.