I guess you want it all explained to you but if you feel like reading something for yourself, read up on the
Byzantine fault. I'd love to have it all explained to me in perfect detail, but I am realistic enough to simply accept my own ignorance and try to work from there. The link was good, very interesting and lots of background, thanks!! However...
Blockchain and PoW solved it, giving security to the system as @ranochigo has explained.
... I still don't fully see the connection. Is it that PoW makes one version of a blockchain more credible because someone invested the work? That kinda makes sense, what my ex called "the high heels proof". While I get the immediate notion of that, it seems like a leap to make one equal the other?
Again, I apologize for my dullwittedness, I know it grinds against some people. I just feel like I am grappling with a very big horse from the wrong end. That... can end badly :p