Here are some ways duality is used:
* Philosophical Duality: This refers to the idea that reality is fundamentally composed of two opposing principles. Examples include the mind-body duality, the good-evil duality, or the subject-object duality.
* Physical Duality: This refers to the existence of two opposing forces or states within a physical system. For example, the wave-particle duality of light, where light can exhibit both wave-like and particle-like behavior.
* Literary Duality: In literature, duality can be used to create tension, conflict, or to symbolize a complex theme. For example, the dual nature of a character, or the opposing forces at play in a story.
* Everyday Usage: Duality can also be used in everyday language to describe the contradictory aspects of a person or situation. For example, someone might be described as having a "dual nature" or "a duality of personality."
In essence, duality highlights the coexistence of opposing forces or ideas, often within a single entity or concept.