@NeitherExtreme,
NeitherExtreme;33204 wrote:I propose to you that we are each (absolutely) certain of our own existence, regardless of any intellectual arguments we construct to the contrary.
Until you get one of those dissociative moments, like when you're driving your car and you completely zone out, and then you come back to yourself and wonder where you've been and how you didn't crash. In other words, we spend a lot of time 'compromised' by sleep deprivation, stress, emotions, etc, where we aren't quite so analytical and we aren't quite so clear.
I'm not sure we're absolutely certain of our own existence when we're tired and dizzy. I'm not sure we're absolutely certain of our own existence when we fear (or learn) something horrible, or when we're deeply ashamed or remoreseful (and we wish it were all untrue). And when we contemplate transience, how some day we'll die, everyone will die, the world will come to an end, our existence seems doubtful as well.
That's at a superficial level. You might argue that deeper down everything we consciously do requires absolute confidence in our existence. But since we seldom think about this issue, I'm not sure that that argument really holds -- we do a lot of things in life without ever pondering our existence.