This is taken from the thread "So my aunt sends me this email ("Is There a God?") Regardless of whether or not one agrees with the arguments, the points made in this particular post are worth taking notice of:
QUOTE BEGINS HERE:
(KAWLINZ):
This is where I think the discrepancy is. You're asking about someone's thoughts, saying that they're dismissing your thoughts, and giving them advice that you think is helpful. You say that you're not sure if he exists or even if you exist, but you're giving them advice on how to debate about proving that they exist. Do you see the contradiction?
REPLY (CARTESIAN THEIST):
This criticism has already been put forward and I think I have replied to it. A lot of philosophical debates occur on the basis of 'What if?'. What you appear to be saying is that it is impossible to question your own existence because it is self-evident to you. In all honesty I do not think the issue is that simple. My first point would be, as in Plato's Cave' and that would be to question not our own existence but the appearance of what we take to be real around us and our physical existence. This is certainly not a self-contradictory viewpoint. Even going further than that and questioning one's own existence need not be self-referentially contradictory. If the thing which exists is so different from what 'I' take to be 'I' [physically, mentally, memories, feelings, consciousness etc.] to be then there is no contradiction that is self-evident. The main issue I have addressed myself to here is the brand of naive realism which is completely uncritical of issues of ontology. There appear to be some subjects on 'Free'domain which are anathema and beyond question and yet within academic philosophy they are considered central and legitimate questions. I am interested to find out why this is. Why is it there are some subjects which are not allowed to be touched? This is more the behaviour of the unquestioning than of philosophers. Certainly not everyone has been this way but since joining there have been quite a number of regulars who seem to want to a] tell people what they may or may not say, b] involve themselves in ridiculing arguments they don't like rather than openly discussing them and c] engaging in ad hominem attacks!
For the record, my title ought to indicate that I'm not a radical sceptic but that I am a representative realist. I had assumed people on here were mostly philosophers and would know the reference but that appears to be wrong on my part. 'Philosopher Kings' apparently pay money for their title. I thought it was literally because they were!
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