Your son sounds more depressed than anything, and convincing him to get help is the best route to go. Depression takes away all our motivation, we don't want to see anyone or do anything, we're sad and just feel hopeless. Get him to see a psychiatrist for an evaluation, this way he can refer him to the proper tharapist and if medication is needed, psychiatrists are most knowledgable. Your son needs help, and there is so much for him which will get him out and living his life. I would tell him that he can continue to live with you ONLY if he agrees to get help. Once he is doing better, then you can address him getting a job and his own place...now is not the time. I wish you both all the best.
I'm not sure I would agree with the above. Having suffered from anxiety all my life, I can maybe give you some insight into what your son *may* be feeling. He may be feeling that there is no hope for him, that he can't be helped. If he's a reader, maybe you could bring him some books. If he's a t.v. watcher, maybe you can find some DVDs. If he's a computer person, point him in the direction of this forum. He may need to know that social anxiety is curable, and that he can live a normal life. But he does have to want it. If I were you, I would help him find a therapist and/or a support group (if he would go). He may need more help than you can give him alone.
He needs to be booted from the nest. told that he is now a man, and learn he has to work to obtain food and shelter. You are well intentioned, but given the fact all he has to do is sit around and watch television, he has no incentive to do anything.