John Henry

Listen, pal, I took a fourth year physics course in Quantum Mechanics and I'll have you know I got 34%, so don't take any notice of the crap I spew about it.

Maybe they've got some other particle that repels Higgs-Bosons. Or maybe they bypass our sensory perception and interact directly with our visual cortex to give us a sense of seeing them.

I'm not reallly sure I believe in ghosts, by the way, I'm just hypothesising aimlessly here.

__________________
"No one was behaving from very Buddhist motives. Then, thought Pigsy, he was hardly a Buddha, nor was he a monkey. Presently, he was a pig spirit changed into a little girl pretending to be a little boy to be offered to a water monster. It was all very simple to a pig spirit."