The philosophy of Berkeley seems to have been consistently misunderstood, from Swift refusing to have the door opened to Berkeley since Berkeley believed he could walk through it and Dr Johnson kicking a stone to refute Berkeley’s thought1, to the 19th century satirical summarising of Berkeley’s thought as “I’ve proved it, it’s nothing, depend on it—nothing—bona fide nothing” and Bill Nye’s “if you drop a hammer on your foot, is it real or is it just your imagination? You can run tests a couple of times and I hope you come to agree that it is probably real.” (For more on Nye, see this post by Massimo Pigliucci which includes the video and critiques it.)
There are two different problems here. The first is a misunderstanding of Berkeley’s argument, as shown by the 19th century satire and Bill Nye. Both suggest that Berkeley is saying that everything that exists is not real. That is not what Berkeley is saying. It is almost precisely the opposite.
Berkeley was arguing against scepticism about the world, and Locke’s idea that all we can know are mental images of objects rather than the objects themselves. That idea disturbed Berkeley since assuming that “things are distinct from Ideas takes away all real Truth, & consequentially brings in a Universal Scepticism, since all our knowledge & contemplation is confin’d to our own Ideas”2.
Starting with the concept of idea as something that can exist only in a mind, Berkeley extends it to include perceptions or sensations. Each sense gives us particular types of ideas – hearing gives us ideas of sounds, touch gives ideas of temperature, texture, motion and solidity, and so on. All our ideas have their origin in ideas conveyed by the senses (a proposition Locke would agree with.)
But Berkeley goes further. When we perceive an object what is it for us? Berkeley suggests that it a collection of all the ideas (perceptions) conveyed to us by our senses. Take an apple: “a certain colour, taste, smell, figure and consistence having been observed to go together, are accounted one distinct thing, signified by the name apple”3 If you take away those ideas given by the senses, there is nothing left of the apple, not even its solidity or the space it takes up.
Given this, why presume there is some external substance that is causing perceptions? If we lose this concept, how does that affect what really exists? It doesn’t affect it at all, says Berkeley: “The philosophers lose their abstract or unperceived Matter…Pray wt do the rest of mankind lose? As for bodies, &c., we have them still”4
Instead, Berkeley argues that our talk of existence is purely talk of ideas, or potential ideas: “The table I write on I say exists; that is, I see and feel it: and if I were out of my study I should say it existed; meaning thereby that if I was in my study I might perceive it, or that some other spirit actually does perceive it”5. And from this Berkeley argues that the idea of an sensible object that cannot be perceived is incoherent – it is essential to it that it must be possible to perceive it. Thus, all sensible objects are necessarily dependant on minds.
Where Swift and Johnson went wrong was in forgetting that solidity is just as much a property perceived by the senses as taste or smell. (Given that extension was regarded as the defining attribute of matter by Descartes and extension as a primary quality by Locke, this is not surprising.) Johnson’s kicking of a stone is therefore beside the point – Berkeley would expect a sensation to result. He would expect the repeated dropping of a hammer on his foot to result in pain. Johnson’s refutation has thus named a type of fallacy: the Argumentum ad lapidem or appeal to the stone, where a position is dismissed as absurd without proof of its absurdity.
Boswell and Johnson discuss Berkeley
After we came out of the church, we stood talking for some time together of Bishop Berkeley’s ingenious sophistry to prove the non-existence of matter, and that every thing in the universe is merely ideal. I observed, that though we are satisfied his doctrine is not true, it is impossible to refute it. I never shall forget the alacrity with which Johnson answered, striking his foot with mighty force against a large stone, till he rebounded from it, ‘I refute it THUS.’ (Boswell’s Life of Johnson)
- Tom Stoneham (2002) Berkeley’s World: An Examination of the Three Dialogues, Oxford University Press, p. 31 ↩
- George Berkeley (2012) The Works of George Berkeley, Vol. 1 of 4, Project Gutenberg (Project Gutenberg EBook of The Works of George Berkeley – pdf, pp. 105-6. (Berkeley’s Commonplace Book) ↩
- George Berkeley (2012) The Works of George Berkeley, Vol. 1 of 4, Project Gutenberg (Project Gutenberg EBook of The Works of George Berkeley – pdf, pp. 350. (A Treatise Concerning The Principles Of Human Knowledge) ↩
- George Berkeley (2012) The Works of George Berkeley, Vol. 1 of 4, Project Gutenberg (Project Gutenberg EBook of The Works of George Berkeley – pdf, pp. 178-9. (Commonplace Book) ↩
- George Berkeley (2012) The Works of George Berkeley, Vol. 1 of 4, Project Gutenberg (Project Gutenberg EBook of The Works of George Berkeley – pdf, pp. 351. (A Treatise Concerning The Principles Of Human Knowledge) ↩