1. So many different cultures all have similiar 'vampiric' ceratures all over the world they made 'myths' about. If many of these cultures didn't interact (as i expect many didn't due to the distance and technology when they created these legends) then there must be some truth behind it or at least something there.
2. There is no evidence saying that a psychic vampire doesn't exsist and there is more evidence to suggest they do due to eye witnesses, and experiences from people and aura tests using a special camera when they are around.
3. Science says they don't... who says science is always right?
4. Anyone who meets a 'vampire', is they are really a truely strong vampire, won't remember it because vampires are said to be able to psychologically delete the memory from the victims brain.

1. No-one has outlives 150 years old to my knowledge (oldest living person was about 128?)
2. If people drink blood the blood cells they drink will either be killed off by their own or it can actually poison someone and kill off their blood cells so consuming a large amount of blood can be lethal.
3. No-one under scientific knowledge has been proven to be able to turn into a bat. If you are bitten by a bat the chances are you'll just get rabies and die.
4. I've never seen or heard of anyone getting burnt up in flames by the sun(though there are people with a rare skin condition that makes them sensitive to it.) or people being burnt by holy water (unless it has acid in it) There are no documents to prove this happened.
5. Everyone ages and no-one is immortal. everything in this world can die that was living and everything grows and changes.

Personal view

I personally believe they do exsist. Why? well why do people believe in God? There is more evidence to say he doesn't exist than to say he does yet Christianity is one of the main religions. Jesus was ressurected from the dead, and vampires are similiar hence they arise from the dead so they say. (not saying jesus is a vampire, don't twist that) there is also evidence thatpeople can come back to life. For example theres reincarnation in other religions, and theres examples of [people who have died on life support machines for up to 3 minutes then miraculously just come back to life and started breathing again. Vampires may exsist and i believe they do because of amm the myths and legends that go back and they're all similiar in some ways. I also believe Psychic vampirism is possible.

My only complaint is that of 'modern day vampires'. People are going around saying "i'm a vampire." or saying that their a 'psi vampire.' If you were a psi vampire you wouldn't tell the world openly. You might get locked up in a mental ward by none believers. I also hate those who say, "i self harm and wear black so i'm a vampire" since when do vampires self harm? I can find no scriptures to say they do such a thing except maybe harm others or do a blood fetish or slit their wrist to feed their fledglings but not out of depression. Thats being emo.

I dislike the fashion of all vampires must have black hair. Vampires have natural coloured hair such as aurburn/red, brown, dark brown, blonde, whiteishblonde or black. No dyed colours like purple, yellow or green etc as being a vampire is said to enhance your features. So your hair will develop it'sown natural colours so why dye over this?

Anyway off the point, Vampires doe exsist. Theres not enough evidence to prove they don't andif sciece says it's not possible whats to say that science isn't wrong for once (or twice.. or three times...;)