Having said all that, he is very skeptical of things. He needs proof, be it video, audio, or multiple experiences by more than one person. He believes most "unexplained" things people experience have natural answers, like wind, pipes, shadow play, house settling or the person themselves might be doing things to bring attention or may be unstable.
He thinks the vast majority of spirits are people who have died and either have unfinished business, or died a tragic death, or don't know they are dead.
He believes the reason why some people see spirits and others don't is that many people refuse to even open themselves up to the possibility that there is a spirit world, or they are just not in-tuned to the world around them.