I don't know about belittling him as a strategy for change. My opinion is that men do not typically handle humiliation well, especially from a woman. While it might seem rational to think "Fine, cut it out and i won't humiliate you," I think a guy is more likely to say "I am going to continue doing what I want, take it or leave it." rather than give in to humiliation from a woman.

Also, you can't be confident that change made under duress is going to last.

Another idea might be to encourage maturity, such that he doesn't so much change as leave these behaviors behind.

Rather than belittle what he is, you could encourage him to see what you want him to be, what you see in him, and what he can be.

Are you thinking of him possibly as a long-term relationship were it not for these problems? If so, you could talk about that, about the serious, mature man that you want and see in him. And you could go on to say that while you know he can do it, you can't wait forever.

How long are you willing to wait to see change? I think you should have some sort of time horizon so you don't waste a lot of time being disgusted by his behavior while waiting for the change that never comes.

You also should consider that this is a habit of his. If he gets to the point of being wiling to consider change, he still would need to break the habit. He might need help with that. If so, a therapist could help, but don't even mention the possibility of therapy until he demonstrates a serious desire to change.

All in all, I'm not optimistic about the prospects for change. Be sure that you consider how long you want to try to encourage change before giving up and moving on. And stick to whatever you decide.