Question: What philosopher along with Alcibiades, son of Cleinias, and General Archestratus was sent too take Potidean hostages and demolish the city wall during 432 B.C.? 
Sentence (from "Yuan Dadu City Wall Ruins Park"): The northern segment of the city wall is preserved, and a narrow and long park was created around the ruin of the city wall in Haidian District and Chaoyang District.
Relevant evidence: No