Douglas Lenat, the founder of Cyc, shares insights from his 37-year journey in common-sense reasoning for AI. He discusses the complexities of knowledge representation, comparing trees to graphs for AI understanding. Lenat emphasizes the dual impact of the internet on knowledge and ignorance. He also reflects on foundational AI discussions from 1984, the evolution of the semantic web, and the interplay of human emotions in AI design. Their conversation underscores the need for deep, contextual intelligence to tackle significant global challenges.