I don't need scientific proof that spirits exist, because I've witnessed enough. Most of it benign, but some of it actually quite frightening. I didn't really believe until I experienced, which happened to me at a young age and has continued throughout my life. I'm not the only one. Being knocked around by unseen forces, having marks on my body, seeing objects move across a room...I don't need a theorem or formula to tell me these things exist because I've witnessed them. If you ever do, you'll believe too, but I won't mock you now for not believing.