Obviously a shortened version of "you're crazy." Meaning: 1. Why that is just silly. 2. That's another stupid idea from you. 3. Hello, I'm with crazy over here. 4. You just plain crazy.
Lindsey insisted that Scott were the velvet jumper, to which he replied, "you crazy."
To be paranoid of opposing political philosophy that you go on Witch Hunts to eliminate people from the High Education based purely Guilt by Association basis
To be Horowitz crazy you need to have Authoritarian Stalinist streak with a obsession of being Politically Correct. As well as being able to act persecuted when you don't get your way.
That student in Pol 101 must be Horowitz Crazy to being callously accusing the Professor of political bias when he told him he was off topic.