I say Law of Attraction exists, because I've experienced it. You say prove it. I say I've already proven to myself and I have no obligation to prove it to you. You declare my experience invalid then proceed to feel sorry for me.
Replace Law of Attraction with ghosts, alien abduction, headache causing radiowaves, healing magnets,
homeopathy.
The reason why personal experience alone is an invalid process to define beliefs is because humans are incredibly biased to certain fallacies, and are
I'm not sure whether you believe in Heaven and Hell or not, I remember one time you claimed not to believe in god.
Clearly this is an instance where personal bias leads to belief where evidence does not justify it.
People don't want to die, or rather, don't want death to be the end of their existence, its a universal human trait, so they make something up, or rather believe in something someone else has made up to make themselves feel better.
Death isn't the end, if you're good you go to Heaven, or you get reincarnated, or you go to Valhalla, whatever the belief happens to be.
However, there is not one test or piece of evidence that has ever verified the existence of any of these places.
They always exist in some other dimension, or otherwise cannot be reached or ever proved.
Why believe that you're going to heaven any more than you're going to Valhalla? No reason of factual truth as theres no more empirical evidence for one than the other, people choose to believe in it because it makes them feel good.
The reason you should care about using the scientific method to determine truth, is so you can avoid letting your own personal bias distort your view on reality.
Everyone should seek to have as many true beliefs, and as few false beliefs as possible, right?
The only way you can be sure whether your beliefs are true or not is via objective, scientific verification, if you actually care whether what you believe in is true or not, then you are obligated to be able to demonstrate it, to yourself, and to others.
"i know its true" simply isn't enough. You're no different to a kook whos convinced himself he can move things with his mind, or has been abducted by aliens. Its true enough for them "personally", but as soon as it comes to proving it to anyone else, and thereby themselves, they can't do it, because what they believe isn't true, its just a very complicated way of lying to yourself.
Fortunately most people are fairly rational in most other respects, and use forms of the scientific method every day. You get very few people jumping from skyscrapers believing they can fly just because they feel they can, you get very few people walking through traffic because they believe they won't be harmed because they have diving protection, you get very few people touching high voltage electricity because they don't believe electricity exists for personal reasons.
People only afford themselves unscientific delusions in respects where it won't actually affect their life much, like what happens after they die, or things like "crystal energy" when the worst thing that can happen is losing some money on some useless tat.
Science, it works bitches.