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22

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 ...


19

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 ...


18

As an observant astrophysicist (pun intended; I'm actually a theorist), I get this question a lot. Personally, most answers I have heard seem rather contrived and do little justice to either the science or the Torah. The study of physics and the study of Torah are both wonderful pursuits of a "higher truth," but they consist of very different methods and ...


17

The Gemara (Chagigah 12a) records a debate about this. One opinion (R' Elazar and R' Yaakov) is that the light referred to here is an intense light with special powers; G-d afterwards concealed it, realizing that there would be unworthy people who wouldn't deserve to make use of such light, and set it aside as part of the future reward of the righteous. The ...


16

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 exellent nature." Even though I'm certain this will be controversial, ...


15

I suspect that its a combination of some superset of the following factors: Intermarriage and conversion bringing in genetic material from the host population. Diet affecting people's hardiness, skin color, etc. Standard of dental care affecting people's facial structure and whether they like to open their mouths. Environmental factors, including sun ...


14

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 ...


14

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. ...


14

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 ...


13

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 ...


11

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 ...


11

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 - ...


11

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 ...


11

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 ...


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 ...


10

The answer is, at the heart, there is broad consensus among the Rishonim that when necessary one may depart from the "literal" meaning (apparent intent, peshat) of the Torah text (though even then there are limits). We are left with a few things to work out: How do we define necessary? Does our difficulty rise to the level of "necessary"? Does departing ...


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.


9

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 ...


9

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. I do 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 sciences we accept. I will attempt to ...


8

The Seder Olam Rabbah added up all of the generations in the Torah and those in the rest of Biblical history to determine how many years had passed since the Creation of Adam. By that reckoning, 5770 years have now elapsed since that Creation. Genesis 1 describes Six Days between the initial Creation of "the Heavens and the Earth" and the Creation of Adam. ...


8

That it is not intended literally, but rather the numbers have allegorical significance. (For example, Chanoch lived precisely 365 years, the number of days in a solar year.) That it referred to dynasties started by the individual person, rather than just to the lifespan of that person. Or that "shana" does not mean what we think it means. I tried to ...


8

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 ...


8

Others can (I hope) provide a more complete answer, but I believe the simple answer is that God exists outside of space and time, and hence is not bound by their restrictions. Just because something is unknowable to humans does not make it beyond the control of God.


8

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 ...


8

Chief Rabbi Jonathan Sacks mentioned in a lecture that he says this blessing on meeting Nobel laureates. That may not be an exclusive list (there may be others who are also deserving of blessing beyond the Nobel laureates), but it is the beginnings of an answer.


8

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 ...


8

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 ...


8

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 ...


8

A simple explanation is that the when G-d created the world 5772 years ago, He did not create it as a "brand-new" world, but rather created the world in a state as if it had been existing for many years previously. This is quite evident from the fact that the sin of the Tree of Knowledge occurred on the same day Adam was created. He was obviously "born" ...


8

Bamidbar 22:23 mentions how Bilam's donkey saw an angel which Bilam could not see. Rashi ad loc. implies that this was not a unique case: there are at times things that an animal can perceive which a human can not.



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