A space without light is depressing. A room without shadows is boring and kills your imagination. If you have shadows you know there is light. We have a primitive hunger for light and shadows, it enables life on this planet. Spend 24 hours outside and look how the light and shadows form the landscape. Some of us love morning shadows, some of us noon and some of us evening. Some love them all. When we are in a hot sunny spot, we start looking for a shadow. Our brains are adjusted to understanding this, and we feel comfortable outside and in a room that has these two opposites. Walking to a room that has one single bright lamp centered in the sealing kills the effect of forming nice shadows and a landscape. If you want to have an interesting and comfortable decoration, let there be many different kinds of lights and shadows.