The disease of Immanuel Kant

《柳叶刀》杂志载文说，康德最有可能是因为退化性（或变性）痴呆症而去逝的。

Renato Fellin,  Alessandro Ble. The Lancet. London: Dec 13, 1997.Vol.350, Iss. 9093;  pg. 1771, 3 pgs

Abstract (Document Summary)

Fellin and Ble discuss the disease that affected Immanual Kant towards the end of his life and led to his death. Kant probably suffered from primary degenerative dementia.

Full Text (2381   words)

Copyright Lancet Ltd. Dec 13, 1997

Immanuel Kant's extraordinary creativity and originality indelibly influenced German and European culture of the 18th century; over the years, his great philosophical works have been the subject of minute examination and analysis. However, the illness that affected the last 8 years of his life and led to his death has never been carefully studied, nor identified. Our aim in this article is to clarify Kant's disease and cause of death.

Kant's background

Kant was born on April 22, 1724, in the Prussian city of Konigsberg (today Kaliningrad, Russia), the fourth of six children.1 After attending the Collegium Fridericianum from 1732 to 1740, he enrolled at the University of Konigsberg in the faculty of philosophy. In 1755, he accepted a doctorate, and was also recognised as a teacher (Privatdozent) by his university. In 1770, he obtained a chair in mathematics at the University of Konigsberg, which he subsequently gave up for one in reasoning and metaphysics. In 1788, he was elected Rector.

Kant published 69 works. The cornerstones of his philosophical thought, "The critique of pure reason", "The critique of practical reason", and "The critique of judgement", which were written at the ages of 57, 64, and 66 years, respectively, are now considered very advanced for those times. In 1796, health reasons forced him to resign his rectorship. In 1801, he left the Academic Senate and abandoned a work that, in his mind, was to represent the totality of his philosophical thought (parts of it were published under the title "Opus Postumum" after his death). Kant's intellectual and physical faculties gradually declined, and he died on Feb 12, 1804. A plaster mould of his shaven head was made;' necropsy was not done.1,2

Medical history

Kant had a delicate constitution, a light bone structure, and poorly developed muscles especially in the legs.3 Nonetheless, he enjoyed good health throughout his youth, the only recorded pathological event being an important head trauma caused by hitting his head against a door.1 As an adult, he had some respiratory infections, which were short lived and uncomplicated.1 He had constipation, which got worse with age; every day he took aloe to regulate his bowel.1

During old age, Kant complained of a "sense of swelling and discomfort at the mouth of the stomach", which was temporarily relieved by eating and eructation.1 These symptoms which defied the therapy of the time, may be classified as a dyspeptic syndrome. From the age of 78 years (2 years before his death), after every meal a hard swelling of a few centimetres in diameter appeared in the right quadrant of the abdomen (the site is not better specified); this forced him to unbutton his trousers to relieve the sensation of pressure.' Possible diagnoses include inguinal hernia, visceral protrusion through a diastasis of the rectal muscles, or intermittent intestinal occlusion.

His biographers report that he had a cataract in his left eye,1 in which vision was extremely reduced; vision in his right eye subsequently worsened, probably for the same reason. On two occasions he was completely blind for a few seconds, and he experienced two other episodes of temporary diplopia;1 these episodes, and especially the transient blindness, may be interpreted as transient ischaemic attacks (TIAs). Other signs or symptoms suggestive of focal neurological disorders were never reported. In his final year Kant had severe urinary frequency and bladder tenesmus,1 features that point to prostatism.

The final illness

Kant's most serious disease appeared in 1796, when he was 71 years old1 (panel 1). Although he showed his usual lucidity, friends found him "very changed" at certain moments, which are not better described; however, in view of the course of the disease, it seems likely that they were episodes of incongruous behaviour and initial memory impairment. In the 2 following years, further manifestations of disease are not reported.

In 1799, memory loss was evident, and it was documented that Kant repeated the same stories many times in a single day. That he remembered past events clearly, whereas the present was less distinct, is compatible with a short-term memory impairment. Kant was aware of this situation and took notes to help himself remember, but regularly lost them. He was also physically weak. From this moment on his behaviour was rarely appropriate and he seemed intolerant and fatuous. A decline in his critical capacities is shown by the fact that he would attribute various oddities reported by the newspapers or friends (eg, the high mortality of cats in some European capital cities, or the presence of strangely shaped clouds, and even "a sense of oppression in his head") to the presence of a "particular electricity in the air". With advancing disease, Kant lost his perception of time, and on occasion a few seconds seemed intolerably long. His progressive physical and psychological weakness brought about a change in his habits; the hours of sleep increased, and the number of his walks decreased. Kant's gait is described as uncertain, and characterised by the need to press down with the sole of his foot in an attempt to get a better foothold and avoid the frequent falls. These falls, which subsequently happened even while standing still, led him to abandon his daily walks.

In 1802, he became spatially disoriented. On one occasion he was taken to his garden, which he had not seen for 2 years; he was completely bewildered and demanded to return to the house. In the winter of that same year, Kant had nocturnal confusion, with unpleasant or terrifying dreams and hallucinations, and obsessions in the form of melodies heard in youth that stuck in his mind keeping him awake.

Panel 1:

 

In the spring of 1803, appetite diminished, and amnestic aphasia appeared; since appropriate terms to express a particular thought escaped him, Kant would resort to circumlocutions or words with an associated meaning; for example to say "landing" (perhaps the French attempt of 1802 to land in England), he would use terms such as "sea" or "mainland". In the summer of that same year Kant required continuous care because of his progressive weakness, poor general condition, and constant danger of falling. By autumn, he could no longer walk even with support, could not sit up straight, and was incomprehensible. In October, he had episodes of syncope with occasional urinary incontinence. In December, he could no longer write his own name; suggesting the appropriate letters of the alphabet was useless because he could not recall their shape, a disturbance suggestive of apraxia and/or aphasia. Subsequently, Kant had to be fed. If we apply the Katz index" to evaluate independence in normal activities of daily living (ADL) for December, 1803, Kant falls into category F because of his inability to move about, eat, wash, dress, and use the toilet without assistance (deduced from the fact that he could not keep his balance without assistance); on the other hand, he was continent. Category F portrays a picture of total dependence. In his final weeks of life, Kant did aimlessly repetitive things (he would button and unbutton his clothing continually, and tie and untie his scarf), and he no longer recognised family members and friends. He lost his sense of taste, and for more than a year had excessive salivation. On Feb 12, 1804, at 1100 h he died.

Discussion

As often happens in the elderly patient, Kant's clinical picture is characterised by the presence of multiple diseases (panel 2). Along with the dyspeptic syndrome, constipation, bilateral cataracts, signs of possible TIAs, and a probable prostatism, the basic symptomatology points to a progressive mental deterioration that may be classified as a senile dementia. Evdokimov's diagnosis of "geromarasmus"2 does not seem appropriate. In Kant's case, the DSM-IV criteria5 for the diagnosis of dementia are satisfied by the contemporary presence of short-term and long-term memory impairment, judgment deficit, aphasia, and possibly apraxia; these disorders substantially disrupted his interpersonal relationships and work. Biographical documents1,2,6,7 do not describe any episode of delirium. In the differential diagnosis of the various causes of dementia, we would exclude some diseases that are responsible for a secondary mental decline (ie, hypothyroidism, vitamin deficiency, hepatic encephalopathy, electrolyte disorders, tumours, endocranial abscess, &c), since these diseases would have got worse or manifested with different signs from those presented during the 8-year course of Kant's illness. Since the diagnosis of primary dementia is one of exclusion, diseases that more commonly cause mental deterioration in the elderly patient must be considered.

Depression

Depression in the elderly patient may manifest as socalled pseudodementia, in which mental inhibition, typical of this disease, causes memory lapses that may suggest a dementia in the initial phase. When the first symptoms of his disease appeared, Kant was well established in his society, surrounded by friends that he saw daily, and highly motivated to write the work that was to be the "summa" of his philosophical thought. The onset of neurological signs (aphasia, apraxia, gait disorders) and other important mental disorders (spatiotemporal disorientation, judgment deficit, nocturnal confusion, obsession, futile activity) along with the increasingly severe memory impairment lead us to exclude depression.

Dementia

Extrapyramidal disease During the course of degenerative diseases of the extrapyramidal system, such as Parkinson's disease or Huntington's chorea, disorders of the upper cortical function, especially memory, may appear. Although typical extrapyramidal signs were apparently absent in Kant's case, the abnormal gait, poor trunkal balance, frequent falls, and dementia, are consistent with one of the Parkinsonian akinetic-rigid states.

Post-infectious dementia Biographical sources1,2,6,7 do not describe signs or symptoms suggestive of meningoencephalitic inflammatory episodes (bacterial, viral, or fungal) that could have caused subsequent mental decline. We can also reasonably exclude neurosyphilis (absence of other signs), progressive multifocal leucoencephalopathy, subacute sclerosing panencephalitis (which appears mostly during adolescence), and in view of the modality and time course of the illness, Creutzfeldt-Jakob disease and kuru.

Substance-induced persisting dementia There is no evidence of chronic ingestion of drugs or other substance (ie, alcohol) that could suggest this disease.' The daily consumption of aloe, a laxative of the anthraquinone family, does not cause cognitive dysfunction.

Mechanical causes The presence of a normotensive hydrocephalus can be documented clinically only with neuroimaging techniques and other specific procedures (radioisotopic diffusion, Miller-Fisher test). The classic diagnostic triad includes gait disorders and urinary incontinence which precede mental decline; aphasia, apraxia, and agnosia are unusual. In Kant's case, the onset of gait disorders followed the initial signs of mental decline (memory impairment); according to Borowski and colleagues,1 the urinary incontinence occurred only once. These findings do not support the presence of normotensive hydrocephalus, even if it cannot be completely excluded. Kant fell numerous times in his last years of life; however, a chronic subdural haematoma as the underlying cause is unlikely because these falls seem to have been the consequence of the gait disorders and severe aesthenia that appeared after the onset of memory impairment.

Panel 2:

 

Vascular dementia Vascular disorders are one of the major causes of dementia in the elderly. Kant's advanced age, a diet rich in animal fats (butter, cheese) and a sedentary life` would have been risk factors for atherosclerotic disease; we do not know whether he had hypertension, the main risk factor for cerebrovascular disease. The only two episodes suggestive of TIAstransient blindness and transient diplopia-are not enough evidence to diagnose a possible vascular dementia because focal neurological signs were apparently absent; in addition there was no clear succession in time between a vascular event and the onset of mental decline or a stepwise trend, according to the NINDS-AIREN criteria.9 There were no atherosclerotic manifestations at other sites (angina pectoris, intermittent claudication).

Personal view

An overall consideration of Kant's disease, in our opinion, points to a form of primary dementia. The disease had a gradual onset; it had a slow, progressive, and typical course over 8 years characterised by a prodromic phase8 (incongruous behaviour), a second phase with neuropsychiatric symptoms (memory impairment, difficulties in concentration, spatiotemporal disorientation, impaired critical judgment, nocturnal confusion, obsessions), a successive neurological phase (severe weakness, gait disorders, aphasia, apraxia, ageusia), and a final brief phase (with loss of appetite and cachexia).

Among the primary forms of dementia, Alzheimer's disease is the most common in western nations. Pick's disease is not readily differentiated clinically, but it is very rare and generally presents symptoms of frontal lobe involvement, such as personality and behavioural disorders, with memory function and spatiotemporal orientation spared for a longer time.8 In Kant's case, the first set of symptoms was present, but the second appeared early and were very severe. On the basis of the available data and the caution necessitated by retrospective examination, we put forward the diagnosis of senile dementia of the Alzheimer type (SDAT) in a patient with bilateral cataracts, prostatism, and a dyspeptic syndrome of an undetermined nature.

Immanuel Kant probably suffered from that senilis stultitia quae deliratio appellari solet that a century later his fellow countryman Alois Alzheimer" would describe as primary degenerative dementia.

We thank Patricia Segato for help in preparing this manuscript.

[Reference]

1 BorowsE LE, Jachmann RB, Wasianski EACh. Immanuel Kant. Sein Leben in Darstellungen von Zeitgenossen. 1912. Italian translation by Pocar E. La vita di Immanuel Kant. Bari: Editori Laterza, 1969.

2 Evdokimov PP. Immanuel Kant's disease. Min Med (Mosk) 1986; 64: 148-50.

3 Dietsch H. "Die Altershygiene Kants". Med Welt 1982; 33 (15): 570-72.

4 Katz S, Downs TD, Cash HR, Grotz RC, Progress in development of the index of ADL. Gerontologist 1970; 1: 20-30.

5 American Psychiatric Association. Diagnostical and Statistical Manual of Mental Disorders. 4th edn. (DSM-IV). Washington DC: American Psychiatric Association, 1994.

6 Thom M. Immanuel Kant. 1974. Italian translation by Marroni M: Immanuel Kant. Roma: Editori Riuniti, 1982. 7 Cassirer E. "Kants Leben und Lehre", 1918. Italian translation by De Toni GA. Vita e dottrina di Kant. Firenze: La Nuova Italia Editrice, 1984.

8 Cassano GB, D'Errico A, Panchen P, et al. Trattato Italiano di psichiatria. Milano: Ed Masson, 1994.

9 Roman GC, Tatemichi TK, Erkninjuntti T, et al. Vascular dementia: diagnostic criteria for research studies. Report of NIDS-AIREN International Workshop. Neurology 1993, 43: 25060.

10 Alzheimer A. 'ber eine eigenartige Erkrankung der Hirnrinde. Allgemeine Zeitschrift fuer Psychiatrie 1907; 64; 14648.

[Author Affiliation]

Lancet 1997; 350:1771-73

Second Department of Internal Medicine, University of Ferrara, via Savonarola, 9, 44100 Ferrara, Italy (Prof R Fellin MD, A Ble MD) Correspondence to: Prof R Fellin