Early Modern · 1685–1753
Berkeley
Their big question
“Does anything exist if no one perceives it?”
George Berkeley took empiricism to a startling conclusion. If all we ever experience are ideas and sensations in our mind, he argued, then maybe that's all that exists — ideas! For Berkeley, ‘to be is to be perceived.’ Things don't vanish when you stop looking, he said, only because God is always perceiving everything.
“To be is to be perceived.”
The big idea
Berkeley was an ‘idealist’: he denied that matter exists independently of minds. All that exists, he said, are minds and the ideas they perceive. The world stays stable and shared because it exists as ideas in the mind of God, who perceives everything at all times.
Why it matters
He pushed the logic of empiricism to its limit, forcing philosophers to take seriously how mind relates to the physical world. His challenge — ‘prove that matter exists outside your mind!’ — is still a classic philosophy puzzle.
The big argument
Most people find it wildly counterintuitive that a chair stops being solid ‘matter’ the moment no one perceives it. The writer Samuel Johnson famously ‘refuted’ Berkeley by kicking a stone — though kicking it only proves you perceive it, which is exactly Berkeley's point.
In their own words
- “Truth is the cry of all, but the game of few.” — George Berkeley
- “All the choir of heaven and furniture of earth… have no existence without a mind.” — George Berkeley
🤯 Fun fact
The city of Berkeley, California — and its famous university — are named after him.
Learn more
Portrait: Portrait of George Berkeley by John Smibert. Public domain · via Wikimedia Commons.
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