We recognize a good match when we see it, even if it takes a few attempts to get to the right point. This principle is about finding the right balance with the right elements. To achieve this harmonious feel, the designer needs to make sure that each item has a right place and plays a specific role in the composition. Nothing should be out of place, useless or random. Unity is the end result of how different elements and principles can work together harmoniously.
False. Romantic composers were notorious for using excessive amounts of dynamics! That's how they'd communicate their intentions to the performing musicians, by putting dynamics in the music so the musicians would know exactly what the composer wanted from them.