עכבר שחציו בשר וחציו אדמה שאין פרה ורבה
There is a mouse that is hard made from flesh and half from dirt, and does not procreate
The spontaneous generation of the half-mouse
Deep into several pages about ritual impurity, the Talmud mentions in passing this strange creature, which has come to be called the mud-mouse. And what exactly is this strange creature? Here is the explanation of Rashi:
אין פרה ורבה - כלומר שלא היה מפריה ורביה של עכבר לפי שנוצר מאליו
It does not procreate: This means it does not sexually reproduce, but instead it spontaneously appears.
And here is Rashi from 127b:
יש מין עכבר שאינו פרה ורבה אלא מעצמו נוצר מאדמה כאשפה המשרצת תולעים
There is a species of mouse that does not reproduce sexually but is spontaneously generated from the earth, just as maggots appear at a garbage site.
The mud-mouse is also mentioned in Sanhedrin (91):
סנהדרין צא, א
צא לבקעה וראה עכבר שהיום חציו בשר וחציו אדמה למחר השריץ ונעשה כלו בשר
Consider the mouse which today is half flesh and half earth, and tomorrow it has become a creeping thing made entirely of flesh.
Clearly, Rashi and the rabbis of the Talmud believed in spontaneous generation. Here is the opening of the Wiki article on the subject:
Spontaneous generation or anomalous generation is an obsolete body of thought on the ordinary formation of living organisms without descent from similar organisms. Typically, the idea was that certain forms such as fleas could arise from inanimate matter such as dust, or that maggots could arise from dead flesh.
Everyone Believed it
How could the esteemed rabbis of the Talmud believed in this crazy idea of spontaneous generation? The answer is simple. Everyone believed it. Everyone, from the time of Aristotle until Louis Pasteur. Here is Aristotle (d. 322 BCE):
So with animals, some spring from parent animals according to their kind, whilst others grow spontaneously and not from kindred stock; and of these instances of spontaneous generation some come from putrefying earth or vegetable matter. [History of Animals 539a, 18-26.]
The great Roman poet Ovid (43 BCE-17/18 CE) is best known for his work Metamorphosis. It’s a bit of a long read (almost 12,000 lines contained in 15 books), and in it he mentions spontaneous generation three times. Actually, given its length, he probably mentions everything at least three times. Here is an example, from Metamorphosis I, 416-437.
So, when the seven-mouthed Nile retreats from the drowned fields and returns to its former bed, and the fresh mud boils in the sun, farmers find many creatures as they turn the lumps of earth. Amongst them they see some just spawned, on the edge of life, some with incomplete bodies and number of limbs, and often in the same matter one part is alive and the other is raw earth. In fact when heat and moisture are mixed they conceive, and from these two things the whole of life originates. And though fire and water fight each other, heat and moisture create everything, and this discordant union is suitable for growth. So when the earth muddied from the recent flood glowed again heated by the deep heaven-sent light of the sun she produced innumerable species, partly remaking previous forms, partly creating new monsters.
Spontaneous generation was an accepted theory throughout the middle ages and was found in the writings of Arab naturalists, such as Averroes. Sir Francis Bacon, (d.1626) the English "philosopher, statesman, scientist, jurist, orator, and author" accepted the theory. And so did Willam Harvey, who discovered the circulation of the blood, - at least under certain circumstances. And why not believe is spontaneous generation? Before the invention of the microscope, it certainly explained how worms, fleas, bees and other insects could appear out of nowhere.
Well, not quite everyone
In his commentary to the Mishnah on today’s page of Talmud, Maimonides has this to say:
והויות העכבר בלבד מן האדמה עד שימצא קצתו בשר וקצתו עפר וטיט והוא ענין מפורסם מאד אין מספר לרוב המגידין לי שראו זה אע"פ שמציאות בעל חיים כזה דבר מתמיה ולא נודעת בו טענה בשום פנים
The case of the mouse which uniquely grows from the earth so that it is half-flesh and half dust and mud is very well known. There is no end to the countless numbers of those who have told me that they have seen it, even though the existence of this creature is astonishing, and there is no known explanation for it.
Maimonides did not reject the idea that the mouse grows directly from the earth, but he seems very sceptical of the idea. Still, it was a widely accepted explanation for centuries before, and centuries after Maimonides. For example, let’s consider…
Jan Baptista van Helmont and the recipe to grow a mud-mouse
Jan Baptista van Helmont (1580-1644) knew a thing or two about science. Although still deeply embedded in alchemy, his many observations led the way to the scientific revolution. He was the first to suggest that the stomach contained somethings to aid in digestion (what we call today enzymes and acids). And according to the Science History Institute, “he discovered that chemical reactions could produce substances that were neither solids nor liquids and coined the term gas to describe them.” “I call this spirit,” he wrote, “hitherto unknown, by the new name of gas…"(Hunc spiritum, incognitum hactenus, nero heroine Gas voco). This laid the groundwork for Robert Boyle’s later research on gases.
Spontaneous generation also occupied Van Helmont’s scientific worldview. Like everyone else, he believed in it, because it explained observations like fleas appearing around rotting meat or mice appearing in a farmer’s barn of grain. He was so certain of the reality of spontaneous generation that he provided a recipe to grow mice de novo.
Then came the microscope. Using one, in October 1676, Leeuwenhoek reported finding tiny micro-organisms in lake water. Now perhaps there was another explanation for how things were created, although not much progress was made for a couple of hundred more years. It was Louis Pasteur (d.1895) who finally disproved the theory of spontaneous generation with some elegant experiments. He boiled a meat broth in a flask like this, with its neck pointed downwards.
Boiling sterilized the mixture, and with the neck pointing down, no organisms could contaminate the broth. As a result, there was no growth of bacteria or could inside the flask. He did the same using a flask with a neck that was upturned. This allowed the broth to become contaminated with organisms in the outside air, and the mixture soon became cloudy. Spontaneous generation had been disproven.
The Rabbi who tried to get it right, but got it wrong
Israel Lipschutz of Danzig (1782-1860) wrote a very important two-part commentary on the Mishnah called Tiferet Yisrael. (Oh, before we go any further, there is an error in the english Wiki page about R. Lipschutz. He was not, as is claimed there, the author of “Shevilei de'Rakiya, an introduction to the principles of Rabbinical astronomy.” Two books of that title on rabbinic astronomy were indeed written: one by Elijah Hokheim (Prague: Emmanuel Diesbach, 1784) and another by Judah Ze’ev Riswasch (Warsaw: Efraim Boymritter, 1896). You can find more on these two works here. But none by our R. Lipschutz. Can someone get into Wiki and edit that page?)
Anyway, in his commentary of the Mishnah R. Lipschutz got very excited about this whole mouse thing:
ואני שמעתי אפיקורסים מלגלגין על בריה זו שנזכרת כאן ובסנהדרין [דצ"א א']. ומכחישים ואומרים שאינה במציאות כלל לכן ראיתי להזכיר כאן מה שמ"כ בספר אשכנזי שחיבר חכם אחד מפורסם בחכמי האומות. ושמו. לינק. בספרו הנקרא אורוועלט חלק א' עמוד 327. שנמצא בריה כזאת בארץ מצרים במחוז טחעבאיס. ונקראת העכבר ההיא בלשון מצרים דיפוס יאקולוס . ובל"א שפרינגמויז. אשר החלק שלפניה ראש וחזה וידיה מתוארים יפה. ואחוריה עדיין מגולמים ברגבי ארץ. עד אחר איזה ימים תתהפך כולה לבשר. ואומר מה רבו מעשיך ה
I have heard heretics mocking the existence of this creature, mentioned here and in the Talmud Sanhedrin. They deny its existence and claim it is not in any way real. So I have found it appropriate to mention here what is published in a German book written by one of the wisest and most well-known of any nationality, named Link. In his book Urwelt (Part I p327) he states that such a creature was indeed found in the district of Thebais in Egypt. In Egyptian this mouse is called Dipus Jaculus, and in German it is called the spring-mouse. Its head, chest and front paws are well-formed, but its rear is still unformed and is just bits of earth. But after a few days, the mouse becomes made entirely of flesh. And I said “Lord, how great are your works!” (Ps.104:24)
So according to R. Lipschutz all the scoffers were wrong, and as proof he cites his contemporary, the well respected naturalist Johan Heinrich Link (1738–1783), whose Die Urwelt und das Altertum, erläutert durch die Naturkunde (Prehistoric times and antiquity, explained by natural history) was first published in Berlin between 1820 and 1822. Great. A mid-19th century rabbi and scholar quoting a German naturalist in support of a statement made by the rabbis of the Talmud. Science and Judaism at their best! Well no. Not so fast.
In a paper devoted to this topic, Dr. Sid Leiman noted that the passage cited by R. Lipschutz only appeared in the first edition of Link’s book, and was removed from later ones. But more importantly, R. Lipschutz misread the context of the passage he was citing. Rather than attesting to the reality of the mud-mouse, Link was quoting from a passage in the book Bibliotheca historica by Diodorus Siculas, a Greek historian of the first century. It was Diodorus who was describing what his contemporaries believed. But what about that reference to the Latin and German names for the mouse? Diodorus wrote in Greek and could not not have thought that Dipus Jaculus (Latin) is an Egyptian phrase. Let’s have Prof. Leiman explain:
What happened is that Link added a footnote to the Diodorus passage, in an attempt to account for the belief in the existence of this strange creature in antiquity. Link’s note reads (in translation): “The Springmaus (Dipus Jaculus), which dwells in Upper Egypt and is characterized by very short forelegs, doubtless could lead one to conclude that it is a not yet fully developed creature.” Link was suggesting that the very existence of the Springmaus, or jerboa, a small, leaping kangaroo-like rodent found to this day in the arid parts of North Africa, and characterized by long hindfeet and short forelegs, may have misled the ancients into thinking that the different parts of the body of some mice fully matured at different times…The upshot of this was that Lipschutz was persuaded, quite mistakenly, that the mouse described by the rabbis as being half flesh and half earth was alive and well in nineteenth-century Egypt, as attested by no less a scholar than Professor Link!
Wrong, but for the right reasons
The rabbis of the Talmud were not fools for believing in spontaneous generation. They would have been fools had they not. If was an explanation for many natural phenomena and was believed by heroes of the scientific revolution, along with everyone else, until Pasteur proved them all wrong.
And what about our Rabbi Lipschutz? Let’s give the last word on him to Prof. Sid Leiman.
One would like to think that Rabbi Israel Lipschutz, whose seminal work is everywhere characterized by intellectual honesty, would have retracted his garbled reading of Link if only the error had been brought to his attention.
If only indeed.
[Expanded spontaneously from an original post here].