The Endowment Effect makes us irrationally value our current belongings. Tom Stafford's tip for fighting against it and getting rid of junk:
[K]nowing the power of the bias, for each item I ask myself a simple question: If I didn't have this, how much effort would I put in to obtain it? And then more often or not I throw it away, concluding that if I didn't have it, I wouldn't want this.
I'm fascinated by hoarders because I have the opposite fixation. I throw everything away. This started, apparently, as a baby. My mother tells me that after I had consumed the contents of my milk bottle, I would simply throw it out of the pram. Because they were glass back in those days, this was a problem. I also threw my teddy bear out of bed and consigned him to the closet (he now perches above my bathroom sink) at some painfully young age. I hate mail. I'm predictably clutter-phobic as well, which makes living in a tiny beach cottage with two dogs and an altitudinous spouse a bit more challenging.
Why the aversion to things? I wish I could claim some spiritual or moral dimension. It's just the way I like to be: free of too much attachment, as independent as possible, able to move lightly, and rarely distracted by bric-a-brac or nostalgia. There are almost no photos in my life either – except on a lap-top. I just find things burdensome. I find memories mostly too painful. I prefer air. And sky.