Try to, and I will say – “But your “proof” presupposes your mind is not addled and you can recognise a proof when you see it. So it fails.”
This is false. There is no "presuppose" required at all. One can be doing a test each time (and no presupposing or precommiting), we win. Second, one cannot prove a universal aposteriori negative and there is no requirement to "prove with absolute certainty" (b/c that is a red-herring) that our minds are not mistaken, confused, etc. The term absolute certainty is nonsense and thus presuppositional apologetics (stemming from Bahnsen who I studied under and advocated for years) is false. http://plato.stanford.edu/entries/induction-problem/
Ask me to prove my claim and I will say: “But prove to me your mind is not addled, then, Doctor”. Which you won’t be able to, for the above reason. I might then add, with a flourish – “So you see, my claim is proved by the impossibility of the contrary”.
All you've pointed to here is an attempt to make an empass - "You can't 'prove to me' and I can't 'prove to you'".
But all this does is mean that we should discuss your standard of evidence - why you think it's valid, whether or not it is cogent to our current phenomenological experiences, and whether it is consistently applied. For this, you might need to go do your philosophy homework first.
And of course I have a good explanation for why your brain is addled,Dr.Lisle – you were hit on the head by a rock.
How do you "know" he was hit on the head with a rock? Please prove it. You won't escape the solipsism you got yourself into by arbitrarily positing a deity, sorry. FAIL.
Second, being hit on the head with a rock does not, in itself, demonstrate that someones mental faculties are impaired. Of course, you still have the same problem as before. Your mind could be failing you into thinking he was hit on the head with a rock and is "addled". FAIL.
your “proof” presupposes your mind is not addled and you can recognise a proof when you see it.
Even if I agreed for the sake of argument (which I don't), a 'supposition' (to think about something for the purpose of testing) demonstrates that there is what we call 'thinking' going on. That is all that is needed. Read Kant's refutation of idealism.
So it fails.So you see, my claim is proved by the impossibility of the contrary
You haven't shown that there is a true dichotomy. You haven't shown that 'the contrary' is logically impossible (even if there is a true dichotomy) and pretending that you have proved something merely by making an arbitrary assertion (which is so common to the superstitious mindset) gets you nowhere.