Question

"if they were people wouldn't believe in them." what the ghost meant by this

Answer 1

By ‘his ghosts,’ John means ghosts characters in his stories. The ghost of Helen had inspired John write unreal ghost stories because people cannot generally believe the real ghosts that have emotions and a love for a peaceful life. A phrase from a book where he says But my ghosts aren’t a bit like you!” “If they were, people wouldn’t believe in them.”
So means that ghosts arent like a person cause if they were like a mortal person people wouldnt believe them if they didnt have that unique look i guess