Peavey was walking peacefully along a public street when he encountered Dorwin, whom he had never seen before. Without provocation or warning, Dorwin picked up a rock and struck Peavey with it. It was later established that Dorwin was mentally ill and suffered recurrent hallucinations. If Peavey asserts a claim against Dorwin based on battery, which of the following, if supported by evidence, will be Dorwin's best defense? 
Dorwin did not understand that his act was wrongful. Dorwin did not desire to cause harm to Peavey. Dorwin did not know that he was striking a person. Dorwin thought Peavey was about to attack him.