There is a famous quote in physiology that goes like this: “Teleology is a lady without whom no biologist can live. Yet he is ashamed to show himself with her in public.” It is attributed to various authors, such as Ernst Wilhelm von Brücke, J. B. S. Haldane, and Asa Gray. And yet no one currently seems to know its exact origin. Here I will review what I found when looking for its source.
It seems to have first been made popular through famous American physiologist W. B. Cannon’s book The Way of an Investigator (1945), where he cites “the German physiologist E. von Brücke” without giving an exact reference. The same is true of W. I. B. Beveridge’s 1950 book Art of Scientific Investigation. Most citations of the quote do not get much further than pointing to these two books, although you might also find references to H.A. Krebs’s article ‘Excursion into the Borderland of Biochemistry and Philosophy’ in a 1954 issue of the Johns Hopkins Hospital Bulletin. Yet Krebs’s article merely cites the aforementioned Cannon and Beveridge books, along with an article that gives no further source.
If we look a little deeper, though, we find a closer citation. The pharmacologist Otto Loewi (1873-1961) writes: “I myself fully agree with an old friend of mine, the late physiologist E. von Bruecke, who once said in a lecture, ‘Teleology is a lady without whom no biologist can live. Yet he is ashamed to show himself with her in public'” (on p. 8 of this booklet). So it is simply a quote made by Ernst Wilhelm von Brücke in a lecture and which passed around? Considering that Ernst Wilhelm von Brücke died in 1892 (which would’ve made Loewi 18 years old at his death), it is safe to say that the “old friend” whom Loewi cites is a different E. von Brücke than the one the quote is usually attributed to. He must be referring to Ernst Theodor von Brücke (1880-1941), the grandson of Ernst W. von Brücke, who knew Loewi and nominated him for a Nobel Prize. At this point I began to strongly think that the quote was originally from Ernst Theodor, not Ernst Wilhelm, and that the people just got them confused. However, note that Cannon cites “German physiologist E. von Brücke” – only Ernst Wilhelm was German; Ernst Theodor was Austrian. However, it is possible that Cannon simply got the two confused. However, the British pharmacologist Henry H. Dale, in a 1954 paper, makes reference to the remark as something said by “v. Bruecke long ago” – which would be surprising if it were said by v. Brücke the younger.
At this point it is important to note that all of the above – Cannon, Loewi, E. Theodor von Brücke, and Dale – knew each other. The first three all had affiliations with Harvard Medical School, while Dale knew Loewi from their time together in London. This suggests to me that the quote does go back in some way to Ernst Wilhelm von Brücke. That the quote was so popular among physiologists of the 30s and 40s and widely attributed among them to the same man makes it seem like it does in fact go back to E. W. von Brücke, especially considering that they were in the presence of men such as Ernst Theodor von Brücke and Loewi who due to their German heritage would’ve had close familiarity with the works of the great German physiologist.
Unfortunately, though, finding the quote in Ernst Wilhelm von Brücke’s work remains frustratingly elusive. The vascular surgeon Gaza de Takats, in two separate articles, the first in Surgery, the second in JAMA, cites “E. von Brücke, 1896” – but in neither one does he actually give the name of the work! This does give me confidence, though, that it is made somewhere in his books. I cannot read German, but searching for key words (e.g., Teleologie, Dame, Öffentlichkeit) in the works of Ernst W. von Brücke does not seem to bring anything up. This might be an effort for someone more fluent in German (though, of course, even if it isn’t there, it could’ve been a remark made in a speech or lecture and which was then circulated orally).
In summary, I found a use of the quote earlier than the widely-cited 1945 Cannon book in Loewi’s recollection that his friend Ernst Theodor von Brücke (1880-1941) once made the remark in a lecture. I think it is likely that the quote ultimately goes back to Ernst Theodor’s grandfather Ernst Wilhelm von Brücke. On the other hand, I have been unable to prove this by finding the passage in one of his works (admittedly, though, my search was very superficial). Someone in the comments on John Wilkins’s blog post above says he found a part of the quote in an Asa Gray letter, but he also said Gray might have been citing Ernst W. von Brücke (though he didn’t say which letter). In addition to a comprehensive search of Ernst W. von Brücke’s works, Gray’s role in the quote might be something to look at further, along with a biography which E. Th. von Brücke wrote of E. W. von Brücke (Ernst Brücke, Vienna: Springer, 1928).