Dialectical loop in a skeptical argument (David Hume)

This [skeptical] argument is not just; because the skeptical reasonings were it possible for them to exist, and were they not destroyed by their subtilitly, would be successively both strong and weak, according to the successive dispositions of the mind. Reason first appears in possession of the throne, prescribing laws, and imposing maxims, with an absolute sway and authority. Her enemy, therefore, is obliged to take shelter under her protection, and by making use of rational arguments to prove the fallaciousness and imbecility of reason, produces, in a manner, a patent under her hand and seal. This patent has at first an authority, proportioned to the present and immediate authority of reason, from which it is derived. But as it is supposed to be contradictory to reason, it gradually diminishes the force of that governing power, and its own at the same time; till at last they both banish away into nothing, by a regular and just diminution.

A Treatise of Human Nature; David Hume
Book one part four, Section I
Page 145
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