What principle is most concerned with the harmony between width and height in a building?

The principle that is most concerned with the harmony between width and height in a building is the Golden Ratio. The Golden Ratio, often denoted by the Greek letter phi (φ), is approximately equal to 1.618. It represents an ideal proportion that has been used in architecture, art, and nature for centuries because it is aesthetically pleasing and evokes a sense of balance and harmony.

When applied to architecture, the Golden Ratio can guide the dimensions of a building or its elements to enhance visual appeal and create a sense of proportion. For instance, if the height of a building is set in relation to its width according to the Golden Ratio, it will result in a structure that feels more harmonious and natural to the human eye.

This principle has been employed by numerous architects throughout history, reflecting the belief that certain proportions lead to beauty and elegance in design. The use of the Golden Ratio in architecture exemplifies how mathematical relationships can significantly influence aesthetic outcomes, thus contributing to a building's overall impact and human experience.