Light
A unified whole, in the context of Gestalt principles, refers to the perception of elements as a complete and organized entity rather than individual parts.
The principle of proximity states that we tend to perceive objects that are close to each other as belonging together.
The principle of similarity suggests that we group objects that share similar visual characteristics such as shape, color or size.
Closure is the tendency to mentally fill in missing gaps or perceive incomplete figures as complete shapes.