Absolutely sure about your existence ? That's weird. Pray tell. How are you so absolutely sure that you're not, yourself, a figment of someone ELSE's imagination ?
Interesting argument that one, assuming you're being serious. One of my old professors said it had been put to him as "how do I know I'm not just a thought in someone else's mind" by a 12-year-old kid (which in no way reduces its cleverness). I think that the main point is that the "I" in "I think therefore I am" is not specified in any way. Even if I am a figment of someone else's imagination then "I" still
exist, even if only as that figment.
If you're being really hardcore you could say that, actually, the statement should be "thought exists". But you can get round that as well by saying that the thought necessarily implies a point of view, which implies an "I". Now I'm going to be incorrigably lazy and quote from the Stanford Encyclopaedia of Philosophy since it says it better than I could:
"Granting that the
cogito does not presuppose a substantial self, what then is the epistemic basis for injecting the “I” into the “I think”? Many critics have complained that, in referring to the “I”, Descartes begs the question—that he presupposes what is supposedly established in the “I exist.” Among the critics, Bertrand Russell objects that “the word ‘I’ is really illegitimate”; that Descartes should have, instead, stated “his ultimate premiss in the form ‘there are thoughts’.” Russell adds that “the word ‘I’ is grammatically convenient, but does not describe a datum.” (1945, 567) Accordingly, “there is pain” and “I am in pain” have different contents, and Descartes is entitled only to the former.
One effort at reply has it that introspection reveals more than what Russell allows—it reveals the
subjective character of experience. On this view, there is more to the phenomenal story of
being in pain than is expressed by saying that
there is pain: in the former case, there is pain plus a
point-of-view—a phenomenal surplus that's difficult to characterize except by adding that “I” am in pain, that the pain is
mine. Importantly, my awareness of this subjective feature of experience does not depend on an awareness of the metaphysical nature of a thinking subject. If we take Descartes to be using ‘I’ to signify this subjective character, then he is not smuggling in something that's not already there: the “I”-ness of consciousness turns out to be (contra Russell) a primary datum of experience. And though, as Hume persuasively argues, introspection reveals no
sense impressions suited to the role of a thinking subject, Descartes, unlike Hume, feels no pressure to reduce all of our concepts to sense impressions. Descartes' idea of the self does ultimately draw on innate conceptual resources."
ETA: Jimbob, I wouldn't worry about derailing this thread since it was pretty much a train wreck from the start. However I wouldn't be so sure that this is a derailment. Bubb claims that through dialectic (implication =
his dialectic) I can be as sure of things in objective reality as I am of the fact of my own existence. This is simply not true. If it were true and Bubb had come up with it, he would be (i) sufficiently clever to put his arguments a lot better than he has, and (ii) making roughly a bujillion dollars on the lecture circuit.
