He has some anger problems, and is having trouble expressing himself. Time outs will DEFINITELY work if he is hitting others. I have a 1 year old screamer and one week of time outs worked. And he's one. But you have to be consistant. EVERY TIME he hits someone he needs to be in a time out. You should sit him down for his time out and then softly talk to him about why he is there. And then ask him questions. Why does he feel he needs to hit people? Why is he hitting himself? Talk to him about other ways that he can let out his anger, show him what he can do to express himself. They understand more than we thing. But I definitely think time outs are a good idea. I am pro time outs lol