The "I refute it thus" is one of the funniest episodes in the history of philosophy (next to Diogenes plucked chicken)
For the unaware:
> “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 Samuel Johnson, quoted from Wikipedia.)
Reminds me of Alan Watts trying to point his audience to what's meant by immediate experience by saying (essentially) that any verbal description, for instance of a bell ringing, is missing the point as far as immediate experience is concerned; "it's just": then he actually rings a bell (catching the audience off guard).
For the unaware:
> “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 Samuel Johnson, quoted from Wikipedia.)