Is This Really My Hand?
The philosopher G. E. Moore famously demonstrated the existence of a mind-independent world by raising his right hand and saying, "This is a hand," and then raising his left hand and saying, "This is another hand." So, Moore continued, at least two things external to the mind exist. QED. Not every philosopher was won over by the argument, and Moore's proof has been debated ever since. Wittgenstein devoted much of his final time on earth to scribbling notes about Moore's approach, which were collected posthumously in On Certainty . Wittgenstein didn't so much disagree with Moore as explore the grammar--or logic--of sentences like, "I know this is my hand": if you can't not know something, can you really be said to know it?--that sort of thing. In other words, the negation of nonsense is also nonsense. It's a thought-provoking volume, which I've quoted occasionally on this blog. The thing I want to note here is that Moore got at some