You would be very foolish indeed to marry him at this point. In fact, you really should be thinking about whether you want to stay where you are or move back.
He has the absolute right to not want children.
You have the absolute right to want them.
But you as a couple can't do both! So you need to choose.
A child has the right to be wanted by both parents and he's right that it is wrong to have a child that you don't want. It's not about how much you want a child - it's about that child's right to parents who want them!
For god's sake though, don't marry him hoping you can talk him round, or worse, have a little 'accident'. That would be grossly unfair to everyone, mostly any child born!
Difficult as it is, the best option for you is to say right, ok, we can't marry because I know I want a child and I want a child more than I want to be married to you without ever having a child.
It's a very painful decision to make. Whichever way you go, it's going to hurt.
Please don't marry him hoping you can make him give you a child.