Now then comes science - say the halls of NASA, or some other respected entity makes public statements. They provide verifiable, unrefutable evidence and documentation using really high tech, state of the art instruments etc. that "ghosts" exist.
Now what? Does your life change - do you reconsider your religious views about life and death. What effect if any, would this have on your existence. Does doubt, disappear? Or does more fear and trepidation of the unknown, the supranatural move into the minds imagination
You exist - Why shouldnt ghosts exist. Although you can't "see" the (air) winds, heat, and cold, they exist - we know because they can be measured but even without measuring techniques - You can feel them - the energies.
Seeing, in this high tech day and age is sometimes over rated. And unfortunately, people have come to rely way too much on the primary faculty of vision, while the sixth sense - intuition, the psychic gifts are ignored. We live in a visual age now - the need to see things trumps our other senses.