Did George Berkeley believe that ordinary objects such as trees and books are real?

Yes, George Berkeley believed that ordinary objects like trees and books are real, though his definition of reality differed from that of materialists.12

Berkeley did not deny the existence of objects we perceive through our senses; rather, he argued that their existence is fundamentally tied to perception. He famously proposed that for sensible objects, "to be is to be perceived" (esse est percipi). Because he held that all sensible objects are composed of ideas, he maintained that these objects exist within the mind.132

Crucially, Berkeley rejected the idea that objects have only an intermittent existence—that they vanish when no one is looking at them. He argued that objects like books in a study remain real and present because they are "still with relation to perception," even when not being actively observed by a human. By affirming that these objects are composed of ideas rather than an imperceptible material "substrate," Berkeley believed he was upholding common sense rather than denying the reality of the world around us.12