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38

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 ...


21

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

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

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 ...


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

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

R. Yosef Albo, Sefer ha-Ikkarim 3:1, writes: 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 animals and man. This idea is repeated, for example by R. Moshe Isserles (...


12

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

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

According to Halacha we follow Rav Sheishes's view (bechoros 7b) who holds like Rabbe Yaakov (the Tannah) that the reason honey is kosher (even if the bee extracts part of its flesh into the honey as part of the process - Rabeinu Gershom) is a Gzeiras Hakosuv (by Hashem's command) and not like the opinion who says that the reason for its permissiblity is '...


11

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

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

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

The Rambam himself addresses your question. He writes the following in Moreh Nevuchim regarding the science in the Gemara: Moreh Nevuchim (3:14): אל תדרוש ממני להתאים את כל ענייני האסטרונומיה שהם ציינו אל המצב כפי שהוא, כי המתמטיקה היתה לקויה באותם זמנים. והם לא דנו בזאת מבחינת שהם מוסרים אמרות אלה מפי הנביאים, אלא מבחינת שהם היו חכמי אותן תקופות ...


10

The Seforno (c.1500) writes this in is commentary to Genesis (8:22): עוד כל ימי הארץ זרע וקציר וקור וחום וקיץ וחורף ויום ולילה לא ישבותו. "לא ישבותו" מלהתמיד על אותו האופן בלתי טבעי שהגבלתי להם אחר המבול, וזה שילך השמש על גלגל נוטה מקו משוה היום, ובנטיתו תהיה סבת השתנות כל אלה הזמנים, כי קודם המבול היה מהלך השמש תמיד בקו משוה היום, ובזה היה אז תמיד עת ...


10

There is no Halachic issue SA YD 201.7 Rema הגה: מותר לעשותו על הגג ובלבד שלא יהיה תוך כלי או אבן אחת שחקקו ולבסוף קבעו אבל חבור אבנים הרבה לא מקרי כלי (תשובת הרשב"א סימן ת"ת):‏ Its allowed to make it on the roof, but not in a container or a stone that was already inground before to be fixed. However stone assembly is not a utensil.


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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