The biggest thing that changed my life wasn't a purchase, but randomly going down a philosophy rabbit hole on wikipedia one day after looking up different "razors" (https://en.wikipedia.org/wiki/Philosophical_razor).
One of the first things I learned was that most arguments in life seem to be mainly due to differences in people's definition of subjective terms, and not understanding how to communicate well enough to figure that out and then do something useful about it.
One of the first things I learned was that most arguments in life seem to be mainly due to differences in people's definition of subjective terms, and not understanding how to communicate well enough to figure that out and then do something useful about it.