4.) I find that these perceptions of mine lead to discovering (or at least they involve) a central presumption concerning the actual reality of myself. It is, even if only tacitly, a necessary and unjustifiable presumption: I can act (not merely that I perceive myself as acting). Not necessarily always, not necessarily with total efficiency; but I nevertheless must still be able to act.
If I try to reduce this or explain it further, I find I have merely repeated the proposition or else I have denied it. Repeating it does not lead me to a deeper truth; denying it leaves me no ability to (quite literally) ‘do’ anything further–at least, not without cheating and secretly smuggling this ability back in.
It is a proposition that is sheerly unjustifiable as it is; because any attempt to justify it (or, alternately, to explain it away in terms of more basic events) requires that its qualitative properties be accepted first from the getgo. A justification of our justification ability cannot succeed due to its circularity, and thus cannot reliably lead to truth; and a deconstructive reduction of our justification ability requires either eliminating justification ability outright (thus destroying the deconstructive reduction attempt itself) or rejustifying the justification ability at a ‘deeper’ level, which again becomes circular.
My ability to actively think is the Golden Presumption of any inference I draw; and in order to argue to anyone other than myself (such as to you, my reader), then I must extend this Golden Presumption to stoutly include your capability to actively think as well.