The Second Mindfulness Training says, among other things, that “I am determined not to steal and not to possess anything that should belong to others…”
Not stealing is, at least, reasonably obvious – if I take someone else’s belongings, I usually know, and if I do it by accident it generally becomes obvious once it’s drawn to my attention. Not possessing anything which should belong to others, though, gets trickier. Sometimes I do know that something in my possession should belong to someone else – if my grandmother gives me something which is actually my father’s, for example, I haven’t stolen it but it should belong to him, not me.
In broader terms, though, what of mine should belong to others? What do I have which would be more use to someone else, or improve their life more than it does mine? Do I have a right to keep useful things in storage for when I want them, or should I pass them on and rely on finding another when I need one? With books, I find it fairly easy to conceptualise the second-hand market as a kind of library; I keep books to which I refer, or which I think I’ll read or consult again, and pass on those where I currently foresee no use for them in my life, reasoning that if the need does occur I’ll buy or borrow another copy. A handful of very rare books might stump this system, and I do keep a few just for being unusual, but my experience so far has been that this works (and that it’s actually very rare that I want a book I passed on – Stig of the Dump is the only example which comes to mind over perhaps ten years of running my book collection like this).
Somehow, I haven’t managed to conceptualise other things like this. My kitchenware, for example, is currently sitting unused in boxes in a spare room. I’m sure it could be useful to other people; but I’m keeping it, as a collection, planning to one day use it again myself.