When I'm about to buy something I always think to myself "where am I going to put this? Where will I store it?" That has prevented me from buying lots of unnecessary stuff. And I use that when I'm organizing/sorting. I ask myself, "do I really have a place for this? Could get rid of something else to find a place for it. Where would that be?
Another thing that helps me to purge is that I know of a very worthy charity store. It's staffed with volunteers and all sales of donated items go directly to buying necessities for the nearby retirement/nursing home where my great aunt lives. It's in a tiny town in a poor, rural area and the volunteers are always very excited when I bring my donations. I always feel good dropping things off there with the grateful volunteers rather than being rushed through the Goodwill drive through with the indifferent people working there. I know Goodwill is a good cause too, but I just feel better bringing stuff to this little shop. And not to beat a dead horse, but it always surprises me how things I don't think much of are so welcomed there. I dropped off an old dusty flower arrangement of my mom's one time and one of the volunteers saw it and said, "oh that is so pretty. I bet it won't last on the shelf all day before someone buys it!"
" I object to violence because when it appears to do good, the good is only temporary; the evil it does is permanent." Mahatma Gandhi
"This is the ultimate weakness of violence: It multiplies evil and violence in the universe. It doesn't solve any problems." Martin Luther King, Jr.