How did Berkeley distinguish active spirits from passive sensible ideas?

George Berkeley distinguished between active spirits and passive sensible ideas by categorizing them as two entirely distinct and heterogeneous types of existence.1

• Active Spirits (Minds): Berkeley defined a spirit as a simple, undivided, and active being. The activity of a spirit is characterized by its capacity for understanding and willing: understanding involves the perception of ideas, while the will involves the power to produce or represent them. Spirits are the subjects that perceive, think, and act.21
• Passive Sensible Ideas: These are the objects of the mind, often referred to as sense-data or imaginable ideas. They are considered passive because they do not possess the power to perceive or act; rather, they are the content perceived by a spirit. For Berkeley, physical objects—such as tables or trees—are simply collections of these passive ideas, which exist only insofar as they are perceived by a mind.12

By maintaining this distinction, Berkeley argued that while ideas require a perceiver to exist, the spirit itself is the active agent that performs the perceiving.12