DO GRUDGES EXIST? ARE THERE SOME THINGS THAT SCIENCE CANNOT EXPLAIN AT ALL?

Many people think that grudges doesn't exist, that it's product of ancient thinking traditions which passed on in generations. If actually something indeed was creating misfortune people around would start thinking that actually the grudges exists. But our society isn't that kind isn't it ?

Every single human, inside their brains, have a defense mechanism that produces disbelief and confusion with those information whic their own minds cannot explain. For an example if you tell somebody "Oh my god! I have seen a ghost in my house!" Obviously people around will not believe in what's saying he/she. This is a protection, people doesn't want to know that there are things unexplainable for themselves and are afraid of those things to actually exist in their daily lives.

Science, throughout all the mankind history made huge mistakes and huge discoveries, some of them remain unexplainable due to lack of knowledge or just by being ignorant persons, afraid of discovering or accepting the "Paranormal World". In fact there are some things that science cannot explain, for example: 

-Chair of Death ( Busby's Stoop Chair)

During World War II, airmen from an nearby base made the pub a hot spot, and the chair became a "hot seat" and people noticed that the ones who sat in it would never come back from war. In 1967, two Royal air force pilots sat in it, and while driving back, they crashed into a tree and died. A few years later, two brick layers decided to try it, and that afternoon, the one who sat in it fell to his death. The cursed chair apparently "killed" every person who sat in it, no matter what. Some instances also include a roofer who sat in it died after the roof he was working on collapsed, and a cleaning woman stumbled into it while mopping, and was later killed by a brain tumor. Eventually, the pub owner moved it into the basement, hoping that nobody would sit in it. However, onde day a delivery man was in the basement and sat in it. An hour later, he crashed his truck and died. After that death, the landlord asked the local museum to take it. To ensure nobody sat in it again, they hung the chair five freet from the ground.

And you? What do you think about grudges?  Do you think they exist or not ?