Rationalism senses. For instance, his famous dictum, "cogito ergo sum" or "I think, therefore I am", is a conclusion reached "a priori" i.e., prior to any kind of experience on the matter. The simple meaning is that doubting one's existence, in and of itself, proves that an "I" exists to do the thinking. In other words, doubting one's own doubting is absurd. This was, for Descartes, an irrefutable principle upon which to ground all forms of other knowledge. Descartes posited a metaphysical dualism, distinguishing between the substances of the human body (""res extensa"") and the mind or soul (""res cogitans""). This
Mr. Cogito which unequivocally identifies the character with the poet for the very first time in the oeuvre. It mentions his return to his homeland, and the other poems in the collection treat about various aspects of Mr. Cogito's being – imagination ("Mr. Cogito and the Imagination"), longevity ("Mr. Cogito and Longevity"), virtue ("Mr. Cogito on Virtue"), eschatological concepts ("Mr. Cogito's Eschatological Premonitions"), bloodshed ("Mr. Cogito Thinks about Blood"), a contact with Maria Rasputin ("Mr. Cogito and Maria Rasputin – an Attempt at Contact"), the need for precision ("Mr. Cogito on the Need for Precision), the notes from a house of the