Solipsism then they must be identical, as in indistinguishable from each other and therefore one and the same thing. Dualists then attempt to identify attributes of mind that are lacked by matter (such as privacy or intentionality) or vice versa (such as having a certain temperature or electrical charge). One notable application of the identity of indiscernibles was by René Descartes in his "Meditations on First Philosophy". Descartes concluded that he could not doubt the existence of "himself" (the famous "cogito ergo sum" argument), but that he "could" doubt the (separate) existence of "his" body. From this, he inferred that the
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