To be the world’s greatest philosopher in the prime of life is no guarantee against developing the ravages of dementia in old age. This is what happened to Immanuel Kant, a little man scarcely five feet tall followed by a devoted servant with an umbrella, who would take his daily walk at so regular an hour that the people in Königsberg would set their watches by it.¹ Born in 1724, Kant lived all his life in that former jewel of East Prussia, a city that the Soviets obliterated so completely in World War II that that even Carthage in defeat fared better at the hands of its Roman conquerors.

An excellent review² details the great philosopher’s medical history. He suffered at various times from dyspepsia, cataracts, urinary frequency and nocturia, a possible inguinal hernia, and had several episodes of transient blindness from perhaps transient ischemic attacks. In 1799 memory loss first became evident, especially for recent events, and he would recount the same story many times in a single day. He became weak, intolerant, lost his perception of time, had several falls which led him to abandon his walks, became spatially disorientated, confused, later aphasic, and continued to exhibit mental deterioration. He died in 1804 at the age of eighty. Neurologists are inclined to rule out the pseudo-dementia of depression, Parkinson’s disease or other afflictions of the extrapyramidal system, subdural hematoma, as well as infectious, vascular, and substance-induced dementia. We are left with a senile dementia of the Alzheimer’s type, a condition described a century after Immanuel Kant’s death by his fellow countryman Alois Alzheimer.²

End notes

1. Review. Meticulous metaphysician. MD, September 1975.
2. Fellin R. and Blέ A, Lancet 1997, 150:1771.