It is remarkable, however, that at the very lowest point…

““It is remarkable, however, that at the very lowest point of Kant's depression, when he became perfectly incapable of conversing with any rational meaning on the ordinary affairs of life, he was still able to answer correctly and distinctly, in a degree that was perfectly astonishing, upon any question of philosophy or of science, especially of physical geography, [Footnote: Physical Geography, in opposition to Political.] chemistry, or natural history. He talked satisfactorily, in his very worst state, of the gases, and stated very accurately different propositions of Kepler’s, especially the law of the planetary motions. And I remember in particular, that upon the very last Monday of his life, when the extremity of his weakness moved a circle of his friends to tears, and he sat amongst us insensible to all we could say to him, cowering down, or rather I might say collapsing into a shapeless heap upon his chair, deaf, blind, torpid, motionless,—even then I whispered to the others that I would engage that Kant should take his part in conversation with propriety and animation. This they found it difficult to believe. Upon which I drew close to his ear, and put a question to him about the Moors of Barbary. To the surprise of everybody but myself, he immediately gave us a summary account of their habits and customs; and told us by the way, that in the word Algiers, the g ought to be pronounced hard (as in the English word gear).””

— Thomas de Quincey