> We have been trying very hard for centuries to contact any kind of afterlife, spirits or gods, and failed.
I'd suppose you haven't tried spending time with people who do practice and do this, do you?
> Even if we cannot perfectly rule it out in principal we can rule out anything we have conceived and tested thus far.
Simply put, you can't. "Absence of proof" does not equal "proof of absence".
> That and Ouija boards are made by Parker Bros [1]. Unless you believe that a group of people with a reliable channel to the afterlife chose to keep making Scrabble and Monopoly games with their super powers, then we really should just discount it as an obvious money grab, because it is.
Not at all. The Ouigi boards are just a tool. There's usually nothing in them that would be manifest to a specific entity or emotion. Not even that, but they are made by machine, so there would be very likely no emotion in contact with them.
Since you seem unlearned in this area, divination can use any sort of tools. Tarot, pendulum, sand, tea, coffee grounds, bones, compass (luao-pen), ruler, entrails, fire, water.. Any of these can be learned and used. Or some are versed in doing divination using no instruments at all - although even in the occult and esoteric areas, this is considered very difficult.
And then it comes full circle with religion. These are religious practices. If you're thinking of Miss Cleo, you're further from the truth. Those are advertisement services ; whereas what I talk of are honestly held beliefs. And when understood from the occult mindset, do give valid answers.
It's one area where I work in regularly, is divination. Sometimes, it doesn't work. In that case, I say as such. Usually, it does.