Only so much space exists between things. What we put in that space affects the quality of our relationships. Here, think of it this way. When you meet with a friend, there is physical space between you. Think of meeting at a coffee shop to catch up.
There is a table between you and your friend. If the coffee shop has done its interior design well, the table is large enough to keep you from your friend’s personal bubble but small enough to keep the conversation intimate. The decor is made of physical objects in physical space.
No doubt the coffee shop is playing background music. Sound is a (kind of) nonphysical thing that exists in physical space. Ideally the coffee shop has chosen the right kind of music, playing it at the right volume. The music fills up some of the aural space in the coffee shop. If done right, you and your friend can hear each other without shouting and yet the many other conversations taking place around you are muted.
We bring with us nonphysical things that fill up nonphysical space. The conversation between you and your friend is filled up by language. That language is filled up by metaphors and idioms and, in the case of friendship, shared experiences that a single word or certain look can call to mind.
Think for a minute what would happen if too many physical and nonphysical things were added to the space between you and your friend. Imagine that sitting on the small table are several large shopping bags, a tall flower arrangement and your friend’s two pugs. The coffee shop is playing country music awfully loud, next to you is a gaggle of teens laughing hysterically at YouTube videos and your friend’s dogs are barking at the toy spaniel that just came through the door. Your friend is a genius who knows six languages and in the excitement of telling a story she keeps changing from one language to the other, sometimes mid sentence. There are too many things filling up the physical and nonphysical space between you and your friend.
Humans are natural stuffadders. Our tendency is to fill space. An empty shelf is the perfect place to put something. A quiet room is the perfect place for drumming pencils on a desk. A meditative mind is the perfect place to fret about monthly bills.
There is a limited amount of physical and nonphysical space between relationships. At some point, adding more things makes relationships suffer.
Simplicity is not primarily about reducing clutter. Simplicity is about making space for relationships to thrive.