Delve into the second part of a lecture on Interactive Proofs presented by Justin Thaler from Georgetown University at the Simons Institute. Explore key concepts such as the Arithmetician protocol, Sharpset, and doubly efficient interactive proofs. Examine the process of counting triangles and learn about general-purpose interactive proofs, including the Rango protocol. Discuss the limitations of these protocols and gain a comprehensive understanding of various interactive proof systems. This talk, part of the Proofs, Consensus, and Decentralizing Society Boot Camp, builds upon previous knowledge and provides an in-depth analysis of advanced topics in the field of interactive proofs.