i think he explained it very well..your friend has his masters in political science and shot down an entire system of beliefs with one metaphor... actually.. if we are gonna nit pick.. its a simile .. not a metaphor.. and its not even a light hearted simile.. but an extremely visual one aimed to discredit.. and what the champ is saying is.. your Masters of Poly Sci should know better. If that is his opinion... its really shallow and narrowminded, (one might even use "broad assumption" ) especially for an M.S..