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36

Ralbag (Gersonidies) has the earliest known use of a proof by mathematical induction in his mathematical work Maase Hoshev (1321 CE). Source: Rabinovich, N. L. (1970). Rabbi Levi Ben Gershon and the Origins of Mathematical Induction. Archive for History of Exact Sciences, 6(3), 237-248. Available in JSTOR here. (For comparison, the prevalent thought ...


34

According to the Rambam in the Guide of the Perplexed "Whenever it is possible to interpret the words of an individual in such a manner that they confirm to a being whose existence has been demonstrated, this is the conduct that is more fitting and most suitable for an equitable man of excellent nature." Even though I'm certain this will be controversial, ...


25

I would say the biggest explanation ahead of its time was not by the rabbis, but by the Torah, steadfastly defended by even the most rational rabbis in the face of prevailing secular thought. Up until 1929 (and perhaps even as late as 1949), the leading view in astronomy was that we lived in a steady-state universe with no beginning and no end. People often ...


22

The short answer is no. Waiting between consuming meat and consuming dairy has nothing to do with how much time we perceive to have elapsed but with the experience of the person who consumed it. Spaceman Ploni, who decided to eat meat immediately prior to takeoff (a revolting thought), can still taste it when he returns to earth, despite the fact that his ...


21

This is from the Babylonian Talmud. Shabbat 135b says that we don't break Shabbas to save the life of a baby born in its eighth month of gestation. The idea was that there are 7-month babies and 9-month babies, and an 8-month baby was either an early 9-monther or a late 7-monther and if it were an early 9-monther, it probably wasn't going to make it. ...


18

The article says that the this meat is created using stem cells from slaughtered animals: Using stem cells harvested from leftover animal material from slaughterhouses, Post nurtures them with a feed concocted of sugars, amino acids, lipids, minerals and all other nutrients they need to grow in the right way. When it comes to nullifying something ...


18

Based on Jewish law, a person's Jewish status (for a non-convert) is determined through matrilineal descent. This means that one is only Jewish from birth if their mother was Jewish. And their mother was only Jewish if their mother was Jewish. Based on this, a person can have seven out of eight great-grandparents who are Jewish, and still not be Jewish from ...


17

Dr. Jeremy Brown, in a post on his Talmudology blog on science in the Daf Yomi, points out that Rava, quoted in Yevamot 97a, provides the first published claim that boys' puberty can be delayed by their being either overweight or underweight. כי אתו לקמיה דרבא אי כחוש אמר להו זילו אבריוהו ואי בריא אמר להו זילו אכחשוהו דהני סימנין זמנין דנתרי מחמת כחישותא ...


15

Shivchei HaBesht records an episode where the Baal Shem Tov wrote a letter to his brother-in-law R' Gershon of Kitov, telling him how he had been taken to task by the Heavenly Court for excommunicating a Torah scholar without sufficient cause. R' Gershon wrote back to say that this indeed had happened, but only after the date of the Baal Shem Tov's letter - ...


15

In Menachot 29B, the following story is told (English taken from page 112 of here): Rab Judah said in the name of Rab, When Moses ascended on high he found the Holy One, blessed be He, engaged in affixing coronets to the letters. Said Moses, ‘Lord of the Universe, Who stays Thy hand?’ He answered, ‘There will arise a man, at the end of many ...


15

First, you should remember how bad infant mortality was in those days. So what it says about how some infants were considered not viable (and thus could not be touched on Shabbos), no longer applies today when infant mortality is much lower. You should talk about the change in infant mortality with your students. The way you phrased your question implies ...


15

See also this letter by the Lubavitcher Rebbe on this subject, in which he states: It is my firm belief that the sun revolves around the earth, as I have also declared publicly on various occasions and in discussion with professors specializing in this field of science. He also explains why he believed this way based on the Theory of Relativity.


14

It is important to bear in mind that a lot of the techniques that science (specifically, archeology) uses to derive information about ancient cultures and religions can't be validly applied to Judaism. Consider, for example: One source of such information is the arts, such as statuary, vase paintings, and the like. The Torah outlaws the making or possession ...


14

Khan is echoing Rabbi Samson Raphael Hirsch, who wrote ~150 years ago about this new theory called evolution: ... if [evolution] were ever to gain complete acceptance by the scientific world, ... Judaism would call upon its adherents to give even greater reverence than ever before to the one, sole God Who, in His boundless creative wisdom and eternal ...


13

Rabbi Y.L. Rapaport suggested that R' Yehoshua Ben Chananiah's statement (כוכב אחד לשבעים שנה עולה ומתעה את (הספינות (בבלי מסכת הוריות דף י עמוד א) This is thought to refer to the periodicity of Halley's comet, about 1500 years before Halley discovered this. In regards to comments suggesting that this claim is unfounded, I note that several reputable ...


12

At the core of your question is the assumption that the flood and its fallout was natural, and was subject merely to the laws of nature as we see them today. For the purposes of this answer I will not accept that premise, however I think that one can still reconcile the evidence we see nowadays with the flood in a cogent way that draws upon the natural ...


11

See our discussion and the sources brought here where it is shown that the pikuach nefesh of reviving a dead person is different than that of saving a live person in that it only overrides Torah commandments if there is a good chance (defined by some to be >50%) of success. Cyrogenics has about as low a success rate as one could imagine, so it would seem ...


11

Rambam, Hilchos Yesodei Hatorah Chapter 3. From Chabad.org Halacha 1 The spheres are called the heavens, the firmament, the habitation, the skies. There are nine spheres. The closest sphere is the sphere of the moon. The second sphere, which is above it, is the sphere which contains the planet Kochav (Mercury). The third sphere, which is above it, ...


11

If we're counting mathematical comments by rishonim (Medieval Scholars), then in addition to @DoubleAA's reference to Ralbag (Gersonidies) who has the earliest known use of mathematical induction, other Jews have made some strides here as well. R. Avraham bar Chiyya has an interesting proof that the area of a circle is equal to half its radius times ...


11

In the translation of Michtav M'elyahu (Strive for Truth vol. 4 p 355), R' Carmell quotes R' Dessler that halacha does not change even if the reason given for the law seems to be untrue. He says that there may be other reasons other than the one given for the said halacha, and only the most obvious reason was the one stated, so the halacha stands without ...


11

There is no special Talmudic dispensation regarding oats. The Mishna lists a grain called שבולת שועל as able to become Chametz. Most Rishonim don't identify that grain with what we call oats. Some Rishonim do identify that grain with what we call oats. Your point is one very strong proof for the former position, according to which indeed oats can't become ...


10

Some of it may indeed be based on the attempt to claim that (G-d forbid) the Torah is not true at all. The early Bible critics did exactly that - nearly everything described in Tanach was dismissed as a fable. But then, when archeology began to turn up evidence that meshes with the Torah narratives, that approach became untenable. So the next logical thing ...


10

The uncertainty principle actually helped the religious case. Before quantum mechanics, people assumed the world was entirely deterministic, without any place for the will of God or man to change anything. Pierre Laplace claimed that one could know the entire future and present just by looking at all the atoms at one point in time. Einstein held so strongly ...


10

R' Eliezer Melamed, in an essay about this blessing and a related one for Torah scholars on the Beit-El Yeshiva website, formulates the standard thus: חכם מחכמי אומות העולם שידוע כחכם וגאון באחד מן המדעים, כלכלה, מתמטיקה או אחד ממדעי הטבע, ובעבודתו תרם תרומה נכבדה למדע ולאנושות One of the scholars of the [other] nations, who is known as a scholar and ...


10

This article from Dr J Menczer indicates that although there is a significantly lower incidence of cervical cancer amongst Jews it is not due to family purity laws, as even Jews who do not observe these laws have a lower incidence of cervical cancer.


10

R' Aryeh Kaplan z'l teaches as follows: R' Nehunia ben Hakana brings in Sefer Temuna that there are larger shmita cycles of 7000 years each, of which we are now in the 6th, putting the age of the earth at 42,000 years old. Midrash states that a "Divine day" is like 1000 years. Therefore a "Divine year" is 365,250 years. R' Yitzchak of Acco - who ...


9

Although this does not answer the question, I came across the following quote from R. Yosef Albo, Sefer ha-Ikkarim 3:1: Coral is intermediate between inanimate matter and plants. We also find the sea sponge, which only has the sense of touch, and is an intermediate between plant and animal stages. We also find the monkey to be intermediate between ...


9

I vaguely recall seeing some discussion about the whole "heat adding" thing years ago (maybe an old AOJS article?), but unfortunately don't have the details. Honestly, I'm still not certain how to understand the mishna. But off the top of my head ... Leo Levi's The Science in Torah suggests that something like manure worked by fermenting, and fermentation ...


9

Zohar (Bereishis 18b and in other places) states that the rainbow has three colors, חוור סומק וירוק - white (or pale), red and green. In Bereishis it associates these three colors with Gavriel, Michael and Raphael. Elsewhere (Bamidbar 215a) it associates them with the three Avos. In one of the maamarim (chassidic discourses) of R. Shneur Zalman of Liadi, he ...


9

If he eats meat, gets onto a fast plane and flies east, and lands before six hours have elapsed for him, I don't think anybody would say that he can now eat dairy just because the clock shows a later time. For that matter, he doesn't get to jump the gun when switching to Daylight Saving Time. (But citation needed.) I would expect the same logic to apply ...


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