> > That I experience my existence is an undeniable fact. One can only infer facts about the universe, such as physics, indirectly, but the one thing I’m utterl

> > That I experience my existence is an undeniable fact. One can only infer facts about the universe, such as physics, indirectly, but the one thing I’m utterly certain of is that I am experiencing existence. > It's really astonishing to me that he words it this way, because independently I have thought almost exactly the same thing for a long time. This is just the famous "cogito ergo sum" of Descartes, dating back to the 17th century. A significant piece of epistemology is devoted to criticizing this reasoning: http://plato.stanford.edu/entries/descartes-epistemology/#4 http://plato.stanford.edu/entries/descartes-epistemology/#4