One Thinks, Therefore One Is

Descartes' reflective effort to eliminate all uncertainty from his experience is also an attempt to eliminate all contingency from it, and, therefore, to detach it from what may be not the case.  Thus, in logical terms, it aims to isolate a universal substratum of Experience.  Furthermore, as many of his successors agree, his reflecting I and his reflected-upon I do not coincide.  So, while the procedure modifies the latter, the former remains unaffected, i. e. the depersonalization of the latter does not transform the former.  Thus, Descartes, perhaps unwittingly, demonstrates that Philosophical Reflection is constituted by an Individual-Universal relation, or, in other words, his reflected-upon fundamental principle is more accurately formulated as 'One thinks, therefore one is'.