Many people have this fear. If its out of sight it will be out of mind. I find this to be especially true with my ADD clients. People waste hours each day searching for things they need. Its a common problem.
You can't live your life with everything you own in piles around your space(although quite a few people do). Here are a couple of ways to solve this situation!
1. Paper Files...make sure that each file is current and has a clear label. Use a label maker. Archive old files such as taxes and mortgage papers.
2. Basement Storage..Use clear bins. Put like with like. Keep an inventory of what you have. Label the front of each bin.
3. Clothing..If you closet is tiny..dont fight it. Pack away your off season clothes. Its much easier to function in a closet that isn't overcrowded. Sort your clothes by color and style. This will make your closet more visually appealing.
4. Don't over buy. If your space is overstocked, its hard to find things. This is a common problem of duplicate purchases.
5. Simplify...What do you really need??
6. Put like with like!! Its that Simple!!
Don't make too many changes at once. This will do more harm that good. Put a few new systems in place at a time! Get used to your changes then make a few more! Give your brain time to adjust to changes!