Final answer:
A principle in art refers to the arrangement of elements in a work of art to produce a visual effect. One important principle is unity, which refers to visual harmony and cohesiveness in a composition.
Step-by-step explanation:
A principle in art refers to the arrangement of objects, elements, forms, and/or colors in a work of art. It is something that can be repeatedly and dependably done with elements to produce a visual effect in a composition. The principles help govern what might occur when particular elements are arranged in a particular way.
For example, unity is a principle that refers to the visual harmony and cohesiveness in a composition. Too much unity without variety is boring, while too much variation without unity is chaotic.