This work investigates the core philosophical question of whether material substance exists independently of human perception. George Berkeley, an influential 18th-century Irish philosopher, challenges the prevailing materialist assumptions of his era by arguing that objects are merely collections of ideas. Through these two foundational texts, he posits that 'to be is to be perceived,' establishing a rigorous framework for subjective idealism that directly influenced subsequent developments in Western thought.

Scholars and students of philosophy frequently identify this volume as a primary source for understanding the transition from classical empiricism to modern idealism. Readers often note the academic density of the prose, which requires careful engagement with Berkeley's specific logical arguments.