5 Reasons to Keep It: 1. It's Sentimental Gold. The more memorabilia you have, the less emotionally valuable each individual item becomes. Keep one card from Grandma, not all of them.
2. It Fits Your Life Today. Possessions should support who you are right now, not five, ten, twenty years ago.
3. You Think It's Gorgeous (Even if No One Else Does.) Stuff that makes you smile (think children's artwork) doesn't count as clutter.
4. You'd Buy it Again. It's tough to be objective about your belongings. Ask yourself, "What would I do if I saw this in a store?"
5. You'll Find a Place For It. Putting it back in a box is just pre-disposal. Any item worth keeping is worth creating a space for.
5 Reasons to Toss It: 1. You Have Twice as Many as You Need. Take inventory of duplicate items--time to shed a few?
2. It's a Gift You Don't Love. Sometimes when we give away a present, we feel like we're giving away the person. Remind yourself it's just an object.
3. It's Not Worth Repairing. Search for similar items on eBay; if your item's current value is less than the cost of repairing it (broken printer, camera, etc.) then toss and replace. Otherwise, give yourself a deadline.
4. Your Gut Says Lose It. Don't second guess your instincts. 99% of the time, you won't ever need it. If you do, it'll become available.
5. You Don't Know What it is. If after 30 days of remaining unidentifiable, plastic objects should get dumped.