In Descartes's Meditations, in order to establish a firm foundation upon which he could build a framework to determine philosophical and material truths, he begins by removing all of his then-current beliefs and examining what could be admitted as indubitable. In effect, he begins by doubting everything, including, understandably, his own existence. This, indeed, is enabled by the "decision" to, as a rule, doubt any proposition which may brought to consideration (at least initially).
The question is, isn't such a doubt contradictory? For if it was possible then one would have accept that nothing is true, and we would have to deny the ensuing cogito argument by default. And, by a similar argument we must also reject the notion of reason itself. As a result, one would be stuck in sort of circular state. Certainly, this is something the modern logicians would find disagreement with.
Also, if this is the case, how can Descartes's premises and argument be made rigorous? Perhaps his project is similar to developing any logical system, in that there must be certain truths in the system not provable by propositions inherent to the system. In this case, one such truth maybe that reason is something which we have to assume is true and works. Though, based on a subtle observation, this may circular as well.
In asking this, I am intending to invoke a philosophical discussion and analysis of Descartes's cogito argument from a modern, rigorous perspective as a logical argument.