Purkyně's Heautognosis

John believed that Purkyně “was one of the most productive investigators of the time and one of the richest in ideas”. Pagel considered him “one of the most gifted researchers of modern times” (“einer der genialsten Forscher der Neuzeit” – translations here and below from the Czech and German sources are generally my own), and Starkenstein spoke of him as “one of the greatest physiologists of all times”. An abbreviated survey of Purkyně's works, with comments, was published as early as 1858/9 by Eiselt. John HJ. Jan Evangelista Purkyně. Czech Scientist and Patriot (1787–1869). Philadelphia: American Philosophical Society, 1959: 4–6; Pagel J. Purkinje (Purkyně). In: Biographisches Lexikon der hervorragenden Ärzte aller Zeiten und Völker (3rd edn). München: Urban and Schwarzenberg, 1962: vol. IV, pp. 688–9; Starkenstein E . Die pharmakologischen Selbstversuche Purkyně's und ihre Beurteilung nach dem heutigen Stande unserer Wissenschaft. [The pharmacological self-experiments of Purkyně and their assessment according to the present state of our science.] In: In memoriam Joh. Ev. Purkyně 1787–1937. Prague: Opera Omnia II, 1937: 54–6. (Also in: Němec B Matoušek O , Eds. Jan Evangelista Purkyně: Badatel-Národní Buditel. Prague: ČSAV, 1955: 106–18);Eiselt T. Purkyně's Arbeiten. Eine literarhistorische Skizze. [Purkyně's works. A literary-historical sketch.] In: Vierteljahrschrift für die praktische Heilkunde. Ausserordentliche Beilage, 1858: vol. 63, pp. 1–20. (Also in: Kruta V, Zapletal V, Eds. Opera Omnia. Prague: Academia, 1985: vol.13, pp. 209–29)

Aterman K Janko J. Purkyně Jan Evangelista (1787–1869). Part I: Biographical notes. Part II: The question of his nationalism. J Med Biog 1994; 2: 146–150; 201–208

Aterman K. Purkyně's Austria Polyglotta: An historical note for our times. J Med Biog 1997; 5: 22–4

Aterman K. Jan Evangelista Purkyně's votum (1847) on the admission of Jews to academic positions at the University of Breslau. Würzburger medizinhistorische Mitteilungen 1993; 11: 311–31

Although Purkyně had registered for his medical studies in 1811, he actually started, for unknown reasons, later. The exact date seems to be uncertain: Klíma, for instance, states that Purkyně began his medical course in 1814, but according to Kruta Purkyně enrolled in 1812. Klíma JV. Osobnost Jana Ev. Purkyně. [The personality of J E Purkyně.] In: Jan Ev. Purkyně 1787–1937. Sbomik statí k 150. výroči narozenin českého učence v Praze 1937. Prague: Purkyňova Společnost, 1937: 182–204; Kruta V. J.E. Purkyně (1787–1869) Physiologist. A Short Account of his Contributions to the Progress of Physiology, with a Bibliography of his Works. Prague: Academia, 1969

Trávničková E Trojan S. Jan Evangelista Purkyně, 1787–1869. Physiologia Bohemoslovaca 1987; 36: 181–9. The social background of science in the first half of the nineteenth century, with an interesting description of the medical school in Prague, “reputed to be the best of all the faculties”, has been presented in detail by Janko and Štrbáňová. Janko J, Štrbáňová S. Věda Purkyňovy doby. [The science of Purkyně's time.] Prague: Academia, 1988

“Ordo clericorum regularium pauperum Matris Dei scholarum piarum.”

Purkyně JE Výryvky z mého života. [Excerpts from my life.] In: Kruta V Zapletal V , Eds. Opera Omnia. Prague: Academia, 1985: vol. 13, pp. 79–118

He did, however, not give up his religion, to which he adhered throughout his life. Teich M. Světový názor J.E. Purkyně. [Purkyně's “Weltanschaung”.] In: Jan Evangelista Purkyně. Prague: Státní zdravotnické nakladatelství, 1962: 103–27

Kruta V Zapletal V. Editorial note no. 13. Jan Evangelista Purkyně. In: Opera Omnia. Prague: Academia, 1985: vol. 13, p. 45

The influence of the contemporary German philosophy on Purkyně has been described in some detail by Toellner and Horák. Toellner R. Naturphilosophische Elemente im Denken Purkyně's. [Elements of “Naturphilosophie” in Purkyně's thoughts.] In: Kruta V , Ed. J.E. Purkyně 1787–1869. Centenary Symposium. Brno: Universita Jana Evangelisty Purkyně, 1971: 35–41; Horák P. J.E. Purkyně and the German philosophy. In: Purš J, Ed. Jan Evangelista Purkyně in Science and Culture. Ústav československých a světových dějin. Prague: CSAV, 1988: vol. 2, pp. 935–54

Aterman K (op. cit. ref. 4); Kiíma JV (op. cit. ref. 5); Kruta V (op. cit. ref. 5); Trávničkova E, Trojan S (op. cit. ref. 6); Janko J, Štrbáňová S (op. cit. ref. 6); Purkyně JE (op. cit. ref. 8); Teich M (op. cit. ref. 9); Kruta V, Zapletal V (op. cit. ref. 10); Toellner R (op. cit. ref. 11); Horák P (op. cit. ref. 11)

Selow E. Schelling, Frederick Wilhelm Joseph (later: von Schelling). In: Gillispie CC , Ed. Dictionary of Scientific Biography. New York: Charles Scribners Sons, 1975: vol. 12, pp. 153–9

Purkyně JE Quoted by Kruta V. Komentar. In: Kruta V Zapletal V , Eds. Opera Omnia. Prague: Academia, 1985: vol. 13, p. 129

Horák P (op. cit. ref. 11)

In a letter to I G Knebel, Goethe described the impression that Purkyně had made on him during his visit in Weimar, 10–12 December 1822. “It seems remarkable to me how he escaped the papists by his own strength and how he developed and educated himself in an autodidactic manner when he started on his own”. Goethe JW, Knebel IG. Briefwechsel zwischen Goethe und Knebel 1774–1832. [Correspondence between Goethe and Knebel.] Leipzig: Brockhaus, 1851

Kruta V Zapletal V (op. cit. ref. 10)

Teich M (op. cit. ref. 9)

Kruta V (op. cit. ref. 5)

John HJ (op. cit. ref. 1); Purkyně JE (op. cit. ref. 8); Teich M (op. cit. ref. 9). “The name of J.E. Purkyně is linked with an amazing number of discoveries in the field of biology and medicine. There is hardly any sphere of medicine which has not benefited from his research heritage.” “More phenomena are now associated with the name of Purkyně than anyone else's.” “Many of his original ideas never became public; the author of this biography has, for instance, found in the Institute at Breslau a most simple instrument for the measurement of respiratory volumes … Purkyně had constructed long before Hutchinson.” Quotes from, respectively: Černý E. J.E. Purkyně and his work on vertigo. In: Purš J , Ed. Jan Evangelista Purkyně in Science and Culture. Ústav československých a světových dějin. Prague: ČSAV, 1988: vol. II, pp. 611–28; Westheimer G. J.E. Purkyně's contribution to sensory physiology. In: Purš J, Ed. Jan Evangelista Purkyně in Science and Culture. Prague: ČSAV, 1988: vol. II, pp. 503–9; Heidenhain R. Purkinje. In: Allgemeine Deutsche Biographie (reprint of the 1st edn of 1888). Berlin: Drucker & Humblot, 1970: vol. 26, pp. 717–31

Kruta V (op. cit. ref. 5)

Schelling FWJ . Sämtliche Werke. Vol. II: Ideen zu einer Philosophie der Natur. [Ideas on a philosophy of nature.] Vol. III: Erster Entwurf eines Systems der Naturphilosophie [First sketch of a system of the philosophy of nature.] Leipzig: Breitkopf und Härtel, 1797, 1799. The brothers J and W Grimm cite Kant's definition of “Naturphilosophie”: “im allgemeinen jener theil der philosophie, deren gegenstand die natur ist” [generally that part of philosophy the subject of which is nature]. Grimm J, Grimm GW. Deutsches Wörterbuch. Leipzig: S Hirzel, 1889: vol. 7

Horák P (op. cit. ref. 11)

Toellner R (op. cit. ref. 11)

Kruta V (op. cit. ref. 5). “Under the influence of this powerful movement many scientists in Central European countries abandoned the long and laborious experimental method of searching isolated facts and endeavoured to explain vital processes by bridging the gaps in scanty and inadequate data by unfounded speculations and generalizations. A conviction of the unity of the whole nature and the endeavour to find some simple principles valid for all phenomena are important features of this new doctrine.” Kruta V (op. cit. ref. 5): 17

Horák P (op. cit. ref. 11)

Toellner R (op. cit. ref. 11)

Toellner R (op. cit. ref. 11), in commenting on Purkyně's role as a “co-founder of a nature-scientifically correct direction of the physiology of the nineteenth century”, also points out that despite the high esteem in which Purkyně was held, the late nineteenth century had not forgiven him for not abandoning his view of Naturphilosphie

Frankenberger Z. Příspěvky k otázce Purkyňovy přírodní filozofie. [Contributions to the question of Purkyně's philosophy of nature.] In: Němec B Matoušek O , Eds. Jan Evangelista Purkyně. Badatel-Národní Buditel. Prague: ČSVA, 1955: 158–67

Talmon JL . Romanticism and Revolt, Europe 1815–1848. London: Thames and Hudson, 1967

Horák P (op. cit. ref. 11)

Klíma JV (op cit. ref. 5)

Horák P (op. cit. ref. 11)

Klíma JV (op. cit. ref. 5)

Toellner R (op. cit. ref. 11)

Ibid. Dualism offers the physiologist “the greatest freedom to immerse himself, on the one hand, in the laws of material existence and, on the other, to fathom on the road to psychological experience the nature of the spirit by the mediation of the self-owned organic life” – Purkyně, quoted by Toellner; ibid., p. 155

Kruta V. K počátkům vědecké dráhy J.E. Purkyně. Korespondence s přáteli z pražských let 1815–1823. [On the beginnings of J.E. Purkyně's scientific career. Correspondence with friends from the Prague years 1815–1823.] Brno: Medical Faculty of the J.E. Purkyně University, 1964

Although at first Purkyně's scientific interests tended towards physics, as a medical student physiology became the subject of his choice and the centre of his scientific career. Physiology at that time was predominantly speculative (Rozsívalová and Niklíček), but to Purkyně physiology became “the science of facts. Its investigation cannot wander in remote misty skies, it must stand on an empirical basis” (Kruta). How serious Purkyně was with his emphasis on physiology as a science of facts is shown by his insistence on the important role of chemistry in physiology — a subject reviewed by Štrbáñová. Rozsívalová E, Niklícek L. Život Jana Evangelisty Purkyně. [Jan Evangelista Purkyně's life.] In: Trávničková E, Ed. Jan Evangelista Purkyně. Život a dílo. [Life and work.] Prague: Avicenum, 1986: 9–99. Kruta V. J.E. Purkyně's conception of physiology. In: Kruta V, Ed. J.E. Purkyně 1787–1869. (Centenary symposium.) Brno: Universita Jana Evangelisty Purkyně, 1971: 27–33; Štrbáňová S. Chemistry in the physiological concepts of J.E. Purkyně. In: Purš J, Ed. Jan Evangelista Purkyně in Science and Culture. Ústav československých a světových dějin. Prague: ČSAV, 1988: vol. II, pp. 671–98

Horák P (op. cit. ref. 11): 948

Westheimer G (op. cit. ref. 20)

Janko J , Štrbáňová S (op. cit. ref. 6): 126

Since anaesthesia had not yet been introduced, it is not surprising that even “non-romantic” scientists were reluctant to use animal experimentation. Kruta V (op. cit. ref. 5): 19

Ibid.: 27

According to Heidenhain (op. cit. ref. 20) and John (op. cit. ref. 1) Purkyně's work can be roughly divided into the first period of studies in the field of subjective sensations from about 1819, to the time when he acquired the Plössl microscope (1832), which then to a large extent determined the second phase, the period of morphological studies

Gruithuisen FVP . Kleine Beiträge zur Heautognosie. [Small contributions to heautognosis.] Neue oberdeutsche Literaturzeitung, No. 6, 1809. Beiträge zur Physiognosie und Heautognosie, 1812 [Contributions to physiognosis and heautognosis.] Cited by Janko J, Štrbáňová S (op. cit. ref. 6) and by Grüsser OJ. Purkyně's First Systematic Investigations of the Vestibular System and Some Correlations with Modern Neurophysiology. Prague: ČSAV, 1988: 715–57

Eiselt T (op. cit. ref. 1)

Grüsser OJ (op. cit. ref. 45)

Horák P (op. cit. ref. 11)

Ratliff F. On the objective study of subjective phenomena: the Purkyně tree. In: Kruta V , Ed. Jan Evangelista Purkyně 1787–1869. (Centenary Symposium.) Brno: Universita Jana Evangelisty Purkyně, 1971: 77–92

Kruta V (op. cit. ref. 5); Janko J Štrbáňavá S (op. cit. ref. 6); Horák P (op. cit. ref. 11); Coleman W. Prussian pedagogy: Purkyně at Breslau 1823–1839. In: Coleman W Holmes FL , Eds. The Investigative Enterprise. Experimental Physiology in Nineteenth-Century Medicine. Berkeley: University of California Press, 1988: 15–64

In one of his letters to Knebel, Goethe wrote about Purkyně: “Such an individual appears to be in an even balance between the outer and the inner world”. John HJ (op. cit. ref. 1)

Teich M (op. cit. ref. 9)

Purkynjě J. Beiträge zur Kenntnis des Sehens in subjectiver Hinsicht. [Contributions to the knowledge of vision from a subjective perspective.] Prague: Fr. Vetterl, 1819 (2nd edn, Prague: JG Calvé, 1823). (Opera Omnia I, Prague, 1918: 1–56.) Czech translation: J.E. Purkyně. Příspěvky k poznání zraku ze subjektivního hlediska. In: Kruta V, Ed. Jan Ev. Purkyně 1869–1969. Brno: University J.E. Purkyně, 1969

Janko J Štrbánoavá S (op. cit. ref. 6)

Starkenstein E (op. cit. ref. 1)

Radii T , J.E. Purkyně and psychophysiology of perceptual, cognitive and sensory-motor processes. In: Purš J , Ed. Jan Evangelista Purkyně in Science and Culture. Ústav československých a světových dějin. Prague: ČSAV, 1988; vol. 2: 827–37

Westheimer G (op. cit. ref. 20)

Purkyně, sarcastically describing the prevailing intellectual climate, thought that Gruithuisen's concept of heautognosis was not accepted in the German literary world because Gruithuisen, although a researcher and significant thinker, did not subject himself to the intellectual “Dressur” (obedience training) expected at the time, if one wanted to be accepted by the ruling aesthetic or philosophical circles. Gruithuisen was a loner — a state with which Purkyně could sympathize. Purkyně J. Podrobné zprávy o mojích starších i novějších literárních, zvláště přírodnických prácích. [Detailed reports of my older and newer literary, particularly nature, works.] In: Kruta V , Zapletal V , Eds. Opera Omnia. Prague: ČSAV, 1985: vol. 13, pp. 150–1

Kruta V (op. cit. ref. 5)

Westheimer G (op. cit. ref. 20)

Coleman W (op. cit. ref. 50)

John HJ (op. cit. ref. 1): 20; Klíma JV (op. cit. ref. 5): 11; Kruta V (op. cit. ref. 5): 26

Goethe, despite his negative attitude towards self-experimentation, was pleased with Purkyně's findings in his study on vision and felt that he had to “congratulate the author for having the natural aptitude to undertake this work. … One has to be strong to be able to examine his own interior without fear.” John HJ (op. cit. ref. 1): 18

Westheimer G (op. cit. ref. 20)

“The findings that Purkyně reported about the visual and vestibular system were so innovative and so accurate that they have survived to this day” (Westheimer G, op. cit. ref. 20). Starkenstein E (op. cit. ref. 1) similarly stressed that neither clinical nor experimental later studies on the effects of camphor, to take another example, have yielded results that would invalidate Purkyně's studies

Brožek J. Purkyně and psychology in a historical research perspective. In: Kruta V , Ed. Jan Evangelista Purkyně 1787–1869. (Centenary Symposium.) Brno: Universita J.E. Purkyně, 1971: 105–18; Brožek J Hoskovec J. J.E. Purkyně and Psychology, with a Focus on Unpublished Manuscripts. Prague: Academia, 1987

Horák P (op. cit. ref. 11)

Purkyně JE (op. cit. ref. 53)

Tschermak-Seysenegg A. Joh. Ev. Purkyně als ein Begründer des exakten Subjektivismus. [Joh. Ev. Purkyně as a founder of exact subjectivism.] In: In Memoriam Joh. Ev. Purkyně 1787–1937. Prague, 1937: 76–96

Purkyně JE (op. cit. ref. 53)

Kruta V (op. cit. ref. 5): 83; Purkynjě JE (op. cit. ref. 8): 134

Kuthan V. Purkyňovy zrakové výzkumy. [Purkyně's research on vision.] In: Trávničková E , Ed. Jan Evangelista Purkyně. Život a dílo. Prague: Avicenum, 1986: 266–315

While Purkyně states that his left eye was myopic, Kuthan (ibid.) describes the right eye as “myopic with a considerable myopic conus”, whereas the left eye was “hypermetropic and probably also astigmatic, with significantly blunted central visual sharpness (amblyopia)”

Kruta V (op. cit. ref. 38)

Kruta V (op. cit. ref. 5: 18) refers to “systems like brunonianism, galvanism, animal magnetism, homeopathy, parasitism, Broussais' ‘physiological medicine’ etc.” Westheimer G (op. cit. ref. 20: 503) points to the “pseudo-scientific, semi-mystical trend manifesting itself in such excesses as Mesmer's animal magnetism”

Votava Z. Purkyně's pioneer contribution to neuro-psychopharmacology. In: Kruta V , Ed. Jan Evangelista Purkyně 1787–1869 (Centenary Symposium). Brno: Universita Jana Evangelisty Purkyně, 1971: 47–56

Purkyně JE. Podrobné zprávy o mojích starších i novějších literárních, zvláště přírodnických prácích. [Detailed reports of my older and newer literary, particularly nature, works.] Živa, vol. 5, 1857, vol. 6, 1858. Cited by Votava Z, op. cit. ref. 76.) Kruta V. J.E. Purkyně – tvůrčí vědec [J.E. Purkyně – the creative scientist.] In: J.E. Purkyně. Prague: Státní Zdravotnické Nakladatelství, 1962: 11–102

Purkyně JE Neue Breslauer Sammlungen aus dem Gebiete der Heilkunde. [New Breslau collections from the field of medicine.] vol. I, 1829: 423. (Cited by Starkenstein E, op. cit. ref. 1)

Starkenstein E (op. cit. ref. 1)

Purkyně JE Relation über einige Versuche zur Ausmittlung der Brechen erregenden Eigenschaft verschiedener Präparate der Ipecacuanha-Wurzel. [An account of some experiments on the cognition of the vomiting-producing quality of various preparations of the ipecacuanha root.] In: Pleischl AM. Das chemische Laboratorium an der k.k. Universität Prag, 1820. Prague: Academia, 1937: Opera Omnia, vol. II, pp. 9–12

Votava Z (op. cit. ref. 76)

Janko J , Štrbáňová S (op. cit. ref. 6)

Radii T , (op. cit. ref. 56)

Trávničková E Trojan S (op. cit. ref. 6)

Radii T , (op. cit. ref. 56)

Kruta V (op. cit. ref. 77); Zadina R. Purkyně's conception of physiological pharmacology. In: Kruta V , Ed. Jan Evangelista Purkyně 1787–1869. (Centenary Symposium.) Brno: Universita Jana Evangelisty Purkyně, 1971: 43–6

Starkenstein E (op. cit. ref. 1). Starkenstein repeated on himself some of Purkyně's experiments with camphor, but used significantly smaller doses. His account places Purkyně's story into sharp focus

Trávničková E. Purkyňovy Fyziognomie. In: Trávničková E , Ed. Jan Evangelista Purkyně. Život a dílo. [His life and work.] Prague: Avicenum, 1986: 362–8

Purkyně JE (op. cit. ref. 53); Purkyně JE . Commentatio de examine physiologico organi visus et systematis cutanei. Vratislaviae Typis Universitatis, 1823: 58. Lhoták KJ , Ed. (Opera Omnia, vol. I, pp. 163–94. Prague: Spolek českých lékařů, Prague: 1918); Purkyně JE Neue Beiträge zur Kenntiss des Sehens in subjektiver Hinsicht. [New contributions to the knowledge of vision from a subjective perspective.] Berlin: G Reimer, 1825. (In: Lhoták KJ , Ed. Opera Omnia. Prague: Spolek českých lékařů, 1918.) Kuthan V. Achievements of J.E. Purkyně in the physiology of vision and ophthalmology. In: Purš J , Ed. Jan Evangelista Purkyně in Science and Culture. Ústav československých a světových dějin. Prague: ČSAV, 1988: vol. II, pp. 565–610

Černý E (op. cit. ref. 20); Grüsser OJ (op. cit. ref. 45); Purkinje J. Beyträge zur nâheren Kenntnis des Schwindels aus heautognostischen Daten. [Contributions to closer knowledge of vertigo from heautognostic data.] Mediz Jahrbücher des k.k. Österr. Staates. Wien, 1820: vol. VI, pp. 79–125. (Praha: 1937, Opera Omnia. Prague, 1937, vol. II, pp. 15–37.) Wondrák E. Medical experiments on man, and Purkyně's observations on his own body. In: Purš J , Ed. Jan Evangelista Purkyně in Science and Culture. Ústav československých a světových dějin. Prague: ČSAV, 1988: vol. 2, pp. 699–704

Dostálek C. J.E. Purkyně a podmíněné reflexy. [Purkyně and conditioned reflexes.] In: Trávničková E , Ed. Jan Evangelista Purkyně. Život a dílo. Prague: Avicenum, 1986: 334–8; Dostálek C. J.E. Purkyně and conditioned reflexes. In: Purš J , Ed. Prague: ČSAV, 1988: vol. 2, pp. 523–9

Dostálek C (ibid.)

John HJ (op. cit. ref. 1: 36); Trávničková E (op. cit. ref. 88); Malý J. Význam Jana Ev. Purkyně pro anthropologii. [The significance of Jan Ev. Purkyně for anthropology.] In: Jan Ev. Purkyně 1787–1937. Sbomík statí k 150.výročí narozenin českéko učence v Praze 1937. Prague: Purkyňova Společnost, 1937: 70–83

Vlček E. Purkyňův vklad a odkaz anthropologii. [Purkyně's contribution and bequest to anthropology.] In: Trávničková E , Ed. Jan Evangelista Purkyně. Život a dílo. Prague: Avicenum, 1986: 348–61

Malý J (op. cit. ref. 93); Vlček E (op. cit. ref. 94). Notes on these lectures have apparently not been preserved (Malý J, ibid.) Kruta V (op. cit. ref. 5) has pointed out that Purkyně's concept of physiology embraced a considerably wider scope than do our present concepts. In dividing general physiology, for instance, into various sections Purkyně listed “Physiological anthropology” as number 6

Ackerknecht, in his short biography of Gall, points out that Gall referred to his theory only as “craniology”. The term “phrenology” apparently is a modification by J C Spurzheim, Gall's collaborator. It is interesting to note that Purkyně in 1825 had dedicated his dissertation Symbolae ad ovi avium historiam ante incubationem to the German anthropologist J Fried Blumenback (1752–1840), the founder of craniology. Purkyně himself had become interested in this field. Ackerknecht EH. Gall FJ. In: Neue Deutsche Biographie. Historische Kommission bei der Bayerischen Akademie der Wissenschaften. Berlin: Duncker & Humblot, 1963: vol. 6, p. 42

Vlček E (op. cit. ref. 94)

Malý J (op. cit. ref. 93)

The biographical accounts by Schramm-Macdonald and Ackerknecht (op. cit. ref. 96) stress the influence that Gall's controversial views exerted on his contemporaries, but also point to his anatomical studies on aspects of the structure of the brain and the spinal cord, that for his time represented distinct progress; they were, however, overshadowed by his later pronouncements, considered merely as the fantasies of a soothsayer. Schramm-MacDonald. GALL, Franz Joseph (1758–1826). In: Allgemeine Deutsche Biographie. Königl: Akademie der Wissenschaften, 1883. Reprinted in Berlin: Duncker & Humblot, 1968: vol. 8, pp. 815–16

Lavater JK (1741–1801). See: Muncker F Lavater JK . In: Allgemeine Deutsche Biographie. Königl: Akademie der Wissenschaften, 1883. Reprinted in Berlin: Duncker and Humblot, 1969: vol. 18, pp. 783–94; Pross W. Lavater, Johann Caspar. In: Neue Deutsche Biographie. Historische Kommission bei der Bayerischen Akademie der Wissenschaften. Berlin: Duncker & Humblot, 1982: vol. 13, pp. 746–50

Trávničková E (op. cit. ref. 88); Malý J (op. cit. ref. 93)

Lavater loved to paint; Purkyně loved to mimic, to the extent that he sat as a model for painters and ordered a plaster-cast mask of his face (Vlček E, op. cit. ref. 94)

Lavater's attack on Moses Mendelsohn caused a wave of protest. Purkyně's vote against the admission of Jews to teaching positions at German universities (Aterman K, op. cit. ref. 4), despite his acceptance of talented Jewish collaborators in his laboratory, is, however, hardly mentioned

“Purkyně simply had to discover” (Malý J, op. cit. ref. 93); “My mind thrives best with original research in nature and a short communication of the new findings, and I have an endless number of new subjects and many new ways ahead of me; by contrast to this, collecting and describing in textbooks of what has already been extracted is repellent to me” – Purkyně JE. (1841) Letter to Antonín Jaroslav Vrt'átek. (Quoted by Halas FX. J.E. Purkyně vypovídá o své práci. [Purkyně speaks of his work.]) In Purš J , Ed. Jan Evangelista Purkyně in Science and Culture. Ústav československých a světových dějin. Prague: CSAV, 1988: vol. 2, pp. 979–91

Muncker Franz (op. cit. ref. 100) points out how “the anxious care with which Lavater on his own person searched for the most secret moves of the human mind and heart, he at the same time transferred to his study of the human body”

Muncker F (op. cit. ref. 100)

Trávničková E (op. cit. ref. 88)

Trávničková E (op. cit. ref. 88)

Nowakowski JF . Žycie i prace naukowe Jana Purkyniego. [The life and scientific work of Jan Purkyně.] Warsaw, 1862

Trávničková E Trojan S (op. cit. ref. 6)

Němec B. Vzpomínky na Purkyňovy pamětniky. [Remembrances on Purkyně's contemporaries.] In: Němec B Matoušek O , Eds. Jan Evangelista Purkyně. Badatel-Národní buditel. Prague: ČSAV, 1955: 16–18