God and the reality of the world

The obvious objection writes itself. If a tree exists only insofar as it is perceived, then the moment everyone looks away, the tree has no perceiver — and so, by esse est percipi, it should cease to exist, then pop back when someone glances over. Worse: if the tree is just my ideas, isn’t the whole “world” a private show, indistinguishable from a vivid dream? Berkeley must show his idealism does not shrink reality into a solipsistic hallucination.

His reply starts from a fact about your own experience: your sensory ideas are not up to you. Open your eyes in daylight and you cannot help seeing what you see. You can conjure a unicorn in imagination and dismiss it at will — but you cannot decide to see the room as an ocean. The ideas of sense are involuntary, and they are more vivid, strong, and orderly than the faint ideas you make up yourself (Principles §§28–33).

Now the inference. An idea is passive, inert — it cannot cause anything. So the ideas of sense, which you plainly do not produce, must be caused by something active: a spirit (a mind, the only kind of active being there is). Since these ideas come in a vast, continuous, law-governed order far beyond any finite will, the spirit imprinting them must be immensely powerful, wise, and everywhere at work. That spirit is God (Principles §§29–33, 146–149).

This dissolves the flickering worry. Objects are collections of ideas — and they exist steadily because God perceives and wills them continually. Even when no finite mind attends to the tree, it remains perceived by the infinite mind of God; so it does not blink out. The world’s persistence and its independence from your whim are grounded in its being sustained, without interruption, in the divine mind (Dialogues II).

Notice the shape of the argument runs both ways. Ordinary theism argues from the world to God; Berkeley argues from the involuntary, orderly ideas of sense to a powerful spirit that must be causing them. Experience itself, rightly understood, is evidence of God — indeed our commerce with God is more constant and intimate than the materialist ever imagined, since He is the immediate author of every sensation (Principles §§147–149).

And the order in those ideas — that fire warms, that bread nourishes, that dropped things fall — is what we call the laws of nature. For Berkeley these regularities are not mechanical pushes of matter; they are the steady, reliable grammar by which God presents ideas. Nature is, he says, a kind of language — the “language of the Author of Nature” — whose consistent signs let us predict experience (one idea reliably signalling another) and act in the world. Science, on this view, is reading that language, not uncovering hidden matter (Principles §§30, 65–66; Dialogues II).

Tally the results Berkeley claims. Reality and objectivity are preserved: the world is the vast, stable, shared system of God-caused ideas, the same for all of us because one God authors it. Scepticism is defeated: we perceive real things immediately, with no unbridgeable veil. And materialist atheism is refuted: the order of experience positively requires an ever-perceiving God to cause it. Far from a bishop’s eccentricity, immaterialism is offered as the defence of everything the plain person and the pious person believe.

So the final inventory of the universe contains just two kinds of thing. Spirits — active, perceiving, willing minds (God and finite minds) — and their ideas — the passive objects those minds perceive. Note an asymmetry Berkeley insists on: we have ideas of sensible things, but only a notion of spirit, since a mind is active and so cannot itself be a passive idea; we know minds through their operations, not as pictures. That is the whole ontology: minds, and what minds perceive. Nothing else — and, crucially, no matter (Principles §§1–2, 27, 135–142).