I'm not just incredulous to the idea of ghosts. I can demonstrate why those who aren't are committable dullards suffering from a severe hebetude of critical thought and reason.
1.) I find it quaint and somewhat comical to hear of someone adamantly asseverate the existence of ghosts which are invading or dwelling in some location (usually a residence, but occasionally a geographical locale—the latter being particularly in vogue amongst cultures that practice animism or ancestor worship).
Apparently, if these irrational cretins are to be taken seriously, a domicile or other building wherein a death—the more macabre or abnormal the aforesaid death, the more or more likely haunted the death's location seems to be believed, or so it seems—then there cannot mathematically exist any populated area that's not haunted by phantoms and ghosts.
For the sake of illustrating these pseudoscientific notions as the paranormal poppycock they patently are, let's take a densely populated megalopolis, like Manila. In this city, we have an estimated population of 1,700,000 people crammed into an impressively uncomfortable 38.55 km² area, for an astounding density of ~43,000/km².
The mortality rate per annum (i.e., the crude death rate) for Manila is 10.5/1,000¹. That means every year, over 19,000 deaths occur within Manila. If we divide 19,000 deaths by the 38.55 km² within which they occur, we get 492.867 deaths per km² per annum. In a single decade, nearly 5,000 deaths are reported for a city of only 38.55 km² in size. Thus, there should be at least one ghost roaming listlessly throughout the city upon and within every home, sidewalk, park, store, lavatory, cupboard, garage, etc. Mathematically, ghosts should outnumber the corporeal denizens by more than 10³ , insofar as we shan't stop at one year but include the city's entire history.
If one resides in a city with a population exceeding 500k and an area less than 200 km², and if the death rate is equal to or less than that of the global community, then there should be many more ghosts than people in that and any other sizeable city.
This defeats the whole idea of haunted houses and so forth, because basic arithmetic tells us everywhere in any sizeable settlement there is a 100% rate of haunted places, replete with ghosts.
We should be besieged by apparitions and phantasmagoria should be a ubiquitous, universal phenomenon the world over. Why and wherefore is it not the case that ghosts are equally observed?
2.) Ghosts and their ostensible sightings seem directly correlated with the publicity they receive and the profits these séance conductors and ghost busters generate. That is to say, the more ghosts are promulgated in mass media and the wealthier these soi-disant psychics and other profiteers become, the more infatuated the public becomes with ghosts, and the more putative ghost sightings are reported. It's a business, and nothing more or less. Tell people they're haunted and that the solution is to pay you hundreds per hour to fix it, and you've got yourself a lucrative scam nobody seems to have the gumption to expose, lest they be ostracized and castigated.
3.) Why are all ghosts humanoid? No one has, to my knowledge, ever been haunted by a rabbit, deer, chimpanzee, etc. It seems another instance of anthropocentric fantasy. Just like every God must be humanoid (with human emotions, and, of course, we are made in his likeness) , just like all aliens must be bipedal and possess such an anatomical propinquity to homo sapiens that they could easily fit in our biological genus, just like....you get the tenor of it, I think.
4.) Why are ghosts not observed at all in some cultures? Why even in those cultures that they are witnessed, none remotely rival the Western World's ghost sightings? Ghost obsessions and phobias seem to be a culture bound psychological disorder.
5.) Why is there no scientific evidence of ghosts? Are all scientists in some clandestine cabal, or some furtive, conspiratorial pact to deny and discredit ghosts and their existence? What for? What might their motive(s) be? And why do even the far-too-serious (yet admittedly gauche, unscientific, and pitiably risible) paranormal investigators continue to fail time and and time again?
I could go into more depth, but I feel I've proved my point and disproved the bovine and credulous klutzes. I doubt the latter, though. Stupidity is difficult to extirpate, especially with one sole refutation.
¹
Manila's mortality rate source