halacha - Above ground burial

Is an above-ground burial halachically acceptable? For example, I've seen multi-story graves that look like a parking garage and tombs that are carved into the side of a mountain.

megillat esther - Who did the Jews fight on Purim if nobody could oppose them?

נִקְהֲלוּ הַיְּהוּדִים בְּעָרֵיהֶם בְּכָל־מְדִינוֹת הַמֶּלֶךְ אֳחַשְׁוֵרוֹשׁ לִשְׁלֹחַ יָד בִּמְבַקְשֵׁי רָעָתָם וְאִישׁ לֹא־עָמַד לִפְנֵיהֶם כִּי־נָפַל פַּחְדָּם עַל־כָּל־הָעַמִּים׃ (Ester 9.5

Throughout the provinces of King Ahasuerus, the Jews mustered in their cities to attack those who sought their hurt; and no one could withstand them, for the fear of them had fallen upon all the peoples.

(I don't feel the English translation really say that nobody opposed them).

וַיַּכּוּ הַיְּהוּדִים בְּכָל־אֹיְבֵיהֶם מַכַּת־חֶרֶב וְהֶרֶג וְאַבְדָן וַיַּעֲשׂוּ בְשֹׂנְאֵיהֶם כִּרְצוֹנָם׃

So the Jews struck at their enemies with the sword, slaying and destroying; they wreaked their will upon their enemies.

So I'm trying to visualize the events: did the enemies strike first or the Jews freely killed their enemies that didn't fight back?

organic chemistry - How do people know HCN smells like almonds?

I was told by my chemistry teacher that $\ce{HCN}$ smells like almonds. She then went on to tell a story about how some of her students tried to play a prank on her by pouring almond extract down the drain to make her think that they had inadvertently created $\ce{HCN}$ gas. She said that she knew that it wasn't $\ce{HCN}$ because if she had smelled the almond scent, then she would have already been dead.

I never asked her, but how do people know $\ce{HCN}$ smells like almonds if they would die before they knew what it smells like?

Answer

The odour threshold for HCN is in fact quite a bit lower than the lethal toxicity threshold. Data for hydrogen cyanide can be found in many places, but here and here are a couple of good references. That subset of the human population that can detect bitter almonds do so at a threshold of 0.58 to 5ppm. The lethal exposure dose is upwards of 135ppm. That's a whole 100ppm range in which to detect and report the fragrant properties.

halacha - Does a Mitzvas Asei doche a lav by Yibum in the case of Mamzeirus?

Hypothetical case: 2 half brothers with a common father. One brother is kosher and the other brother is a mamzer. The mamzer marries a mamzerres and they have no offspring. The mamzer dies and the mamzerres is now "zakuk leyibbum" bound by her brother in law and cannot marry any one else until he does yibbum or chalitza.

Does the kosher brother in law have to do chalitza as he is prohibited to marry a mamzeres?

Or maybe she can do yibbum as the asei (positive mitzva), "Yevama yavo aleha" overrides the lo taaseh (negative mitzva) of "lo yavo mamzer bikhal hashem" ?

The question would likewise apply if the kosher brother dies childless leaving his kosher wife to be zakuk (bound) to his brother who is a mamzer.

The other cases where this question would be applicable Would be in cases of Petzua daka (a man with crushed reproductive organ), Kerus shofcho (a man with a cut off reproductive organ), Almono Lecohen Gadol (women that had been betrothed and become a widow, to do yibbum to a high priest), Gerusha lecohen Hediot (divorcee to any Priest),

word choice - What's the difference between 女性 and 女の人?

As far as I'm aware, both words translate into English as "woman". What's the difference in meaning between 女性 and 女の人?

Answer

There is no difference in meaning when the two words refer to "woman/women". There are, however, differences in how native speakers perceive the two words and the nuance they carry.

To discuss the exception first, 「[女性]{じょせい}」, has an extra meaning "feminine" or "female gender" when used in grammar terms for certain languages such as Romance languages. For instance, "la maison = 'the house'" is a 「[女性名詞]{じょせいめいし}」 = "feminine noun" in French. We never call it an 「女の人名詞」 or 「女名詞」.

As with nearly all other pairs of Japanese-origin words and their Chinese-origin counterparts with the same or similar meanings, the main difference between the two groups is the formality of the words. On-reading, Sino-loanwords like 「女性」 are almost always used in more formal or technical situations than their kun-reading, Japanese-origin counterparts like 「女の人」.

Japanese children learn to use the word 「女の人」 years before they learn to actively use 「女性」. You would rarely meet a kid under 12 or so who uses 「女性」 on a regular basis. Even teenagers would rarely use 「女性」 in their daily conversations, but they would in compositions and presentations in schools.

Some adults use 「女性」 even in the most informal conversations, but using 「女の人」 would be far more common on those occasions. Only 「女性」 is used in newspapers, magazines, academic papers, etc., and using 「女の人」 in those is utterly out of the question.　

everyday chemistry - What is the difference between wet paint, dry paint, and in between those stages?

A day after painting a closet, I set a piece of wood on the wall of the closet that was painted a day ago as well. Within minutes, both of their layers of paint fused together (please correct me if there is a better term than 'fused').

I'm assuming that the paint approaches a state of being a solid, but the process is never stopping, (as I've heard:) similar to how concrete is much stronger thousands of years after it is made rather than a couple of years.

So I understand that it started off as a liquid with a high viscosity, and liquids with high viscosity's turn into a solid when spread thin, but why does that even happen. As well, was I right when I explained that it is constantly 'drying', explaining why it was able to fuse with the other layer of the same paint even a day later?

minhag - Do any Chasidim still accept Shabbos according to Rabbeinu Tam zman?

Apparently there is a story that Rav Moshe Feinstein asked the Satmar Rebbe to not have his followers begin shabbos with zman Rabbeinu Tam. Is there still a minhag amongst chasidim to take on shabbos according to Rabbeinu Tam anywhere?

This is somewhat similar to Can one follow Rabbeinu Tam time for beginning Shabbos?

but here it is not about practical halacha for the 'hamon am', but specifically geared towards Chasidim and current practices.

gentiles - Why does the Torah forbid interest only on loans to Jews?

Why aren't we allowed to charge a Jew interest but we're allowed to charge a non-Jew?

food - If Bal Tashchis and Achila Gasa would get in a fight, who would win?

There is a prohibition not to be wasteful. There is also a prohibition not to overeat. If a person was full, and the rest of the food was going to go to waste, is it better to discard perfectly good food, or better to overeat in order to not waste?

In order that no one attempt to avoid the underlying issue by finding a way not to waste the food, let's assume that the subject is stranded on a desert island with no other forms of life to which he could feed this food or use it for any constructive purpose.

Answer

The gemara in Shabbos says (140b)

בל תשחית דגופא עדיף

Damaging (lit. בל תשחית [lit. destruction]) of one's body is more important [than בל תשחית of food]

(translation mine)

Seems pretty simple that if overeating is harmful to a person's body (which it is), it should be avoided even at the cost of wasting food.

grammar - Embedded question followed by と

What is the grammar behind the use of the quote marker と in this sentence?

雨がいつ降るかと大変楽しみにしていましたが、なかなか雨が降りません。

He was looking forward to when the rain would come, but...

Can I also write

雨が降ることを大変楽しみにしていましたが、なかなか雨が降りません。

He was looking forward to the rain coming, but...

and does it change the nuance?

Answer

As you already noticed that the と is used as the quote marker in the first sentence. That means 雨がいつ降るか is written as the person's thought, which makes the sentence more subjective.

On the contrary, the second sentence sounds more objective.

Relatively with or without personal feelings might be the crucial difference between the two sentences.

By the way, just by the single sentence without context, the subject of it is more likely to be "I" rather than "HE".

tefilla - Is the Koren Sacks Nusach Sefard truly nusach ha'Ari?

Koren came out with a KSS version in 'nusach Sefard.'

Is this the nusach of ha'Ari? I'm not too familiar with nusach Sefard/nusach ha'Ari. I like Koren's layout and aesthetics, and I've used their nusach Chakhmei Maroko (Avoteinu) siddur and love it. I've used both sefardi and azkenazi siddurim (family is moroccan and lithuanian) and am interested in the Ari's concept of a 13th gate for people like me, but I want to make sure I'm using his nusach. If the Koren edition isn't the Ari's nusach, is his available anywhere?

Answer

The Koren Sacks Siddur is Nusach Sepharad, that is to say, the "Spanish-Portuguese" rite. Nusach Sefard is a variant similar to Ari which bears more similarity to Edot HaMizrach and Ashkenaz to Sepharad. The main differentiating point between Sepharad and Sefard is in Kabbalat Shabbat; in Sepharad, Bameh Madlikin is said, whereas in Sefard, and by extension other kabbalistic nuschaot, Kigavnah and Razah D'shabbat are said. In summation, Koren does not have a Sefard or Ari siddur, the only company that I know of who does is Kehot.

translation - The meaning of 「尋ねられもしないこと」

I'm reading a Japanese novel and there's this part of the sentence I don't know the meaning

公安からの情報が必要な場合は、何とかして引き出す。しかし、尋ねられもしないことをこちらからわざわざ連絡するつもりはない。

My rough translation is: "In case information from the police is needed, we'll manage to get it. But we have no intention to contact them for 尋ねられもしないこと."

Answer

「尋ねられもしないこと」 means "something that is not even asked."

Breakdown:
尋ねられ -- verb 尋ねる + passive られる
も -- binding particle (係助詞) "even"
しない -- verb する + negative ない
こと -- noun (事) "thing, something"

「the continuative form (連用形) of a verb + もしない」 means "don't even do~~", eg: 「知りもしない」 「見もしない」

尋ねられもしないことをこちらからわざわざ連絡するつもりはない。

literally means "We have no intention of taking the trouble to inform them of something we are not even asked." / "We are not going to bother to (contact them to) let them know something we are not even asked."

blessing - Do you say Shechiyanu on a used tallis you tied new tzitzis onto?

If you tied new tzitzis on an old beged, do you recite Shehechiyanu on the tallis?

Answer

No you don't, you only make shechiyanu on a new Tallit (when you put on the tzitzit), but never on an old one. See Mishna Berura OC 22 sif katan 2,

אם עשה ציצית בבגד שהיה לו מכבר אף שלא היה בו ציצית מעולם אין צריך לברך שהחיינו

If one makes (attaches) tzitzis on a garment that he already had, even if tzitzis had never been attached to it, one does not have to bless shehecheyanu

number - Shiv'im?

Who knows seventy?

Please cite/link your sources, if possible. At some point in the next few days, I will:

• 
  
  

  Upvote all interesting answers.

  
  


• 
  

  Accept the best answer.

  
  


• 
  

  Go on to the next number.

  
  

Answer

70 is/are:

1. Avrams age when he first came to Canaan- YDK


2. Years of David haMelech- Shalom


3. Shekel weight of basin brought by Nachshon be Aminadav- Shalom


4. Shekel weight of basin brought by Nesanel ben Tzuar- Shalom


5. Shekel weight of basin brought by Eliav ben Chelon- Shalom


6. Shekel weight of basin brought by Elitzur ben Sh'deur- Shalom


7. Shekel weight of basin brought by Shlumiel ben Tzurishadai- Shalom


8. Shekel weight of basin brought by Elyasaf ben D'uel- Shalom



9. Shekel weight of basin brought by Elishama ben Amihud- Shalom


10. Shekel weight of basin brought by Gamliel ben P'dahtzur- Shalom


11. Shekel weight of basin brought by Avidan ben Gidoni- Shalom


12. Shekel weight of basin brought by Achiezer ben Amishadai- Shalom


13. Shekel weight of basin brought by Pagiel ben Ochran- Shalom


14. Shekel weight of basin brought by Achira ben Enan- Shalom


15. Bulls for Olah on Sukkos- Shalom


16. Nations of the world- Chanoch


17. Descenders to Egypt w/ Yaakov- Chanoch


18. Defects that render an animal tereifah- Dave



19. Interval in years between the chilazon's ascent in the sea- Dave


20. Age at which the אפעה ("vipers" - Artscroll) becomes fertile- Dave


21. Age at which the carob tree bears fruit- Dave


22. Man's lifespan- Dave


23. Age at which man is called a שיבה- Dave


24. Years of the Babylonian exile- Dave


25. Weight in Maneh of Tzari in the Ketores- Dave


26. Weight in Maneh of Tziporen in the Ketores- Dave


27. Weight in Maneh of Chelbenah in the Ketores- Dave


28. Weight in Maneh of Levonah in the Ketores- Dave



29. Interval in years between Shissin cleanings- Dave


30. 70 nations (mentioned by Chanoch)


31. Pesukim from beginning of Breishis until Curse of Nachash- YDK


32. Pesukim from Haman's promotion until his hanging- YDK


33. Names of Hashem from Breishis until the parashah of the Nachash- YDK


34. Age that Terach begat Avraham- YDK


35. Age that Kenan begat Mehalalel- YDK


36. Days of crying for Yaakov- YDK


37. Shabbossim/Yamim Tovim in a Solar year- YDK


38. Names for Hashem- YDK



39. Names for Yisrael- YDK


40. Names for the Torah- YDK


41. Names for Yerushalayim


42. Years taken from Adam for Dovid


43. Days from Haman's Iggeres to Mordechai's- YDK


44. Years of Choni's slumber- YDK


45. Number of Elders to assist Moshe- YDK


46. Number of lots with the word "zaken"- YDK


47. Number on the Sanhedrin acc. to Rabbi Yehudah- YDK


48. The number of golden chairs set above Shlomo haMelech's throne- YDK



49. Gematria of Yayin- YDK


50. Gematria of Sod- Shalom


51. Facets of the Torah- YDK


52. Rabbi Elazar's age/appearance when appointed- Dave/YDK


53. Shmittos from the 1st Churban to the 2nd- YDK


54. Good years that turn bad b/c of Nivul Peh- YDK


55. Date trees in Elim


56. Unit of years that a court is destructive if it executes more than 1 person- Dave


57. Sifrei Torah written by Rav Huna- Dave


58. Age of Ramban when he moved to Eretz Yisrael- Dave



59. Sons of Gideon from wives- YDK


60. Brothers to Avimelech- YDK


61. Silver pieces given to Avimelech by Anshei Sh'chem- YDK


62. Children and grandchildren to Avdon ben Hillel- YDK


63. Donkeys owned by the above- YDK


64. Answers to the stirah in Rav Ashi- Shalom


65. Original Tikkunim in Tikkunei Hazohar- Isaac Moses


66. Lamps to Shlomo haMelech's Menoros- Dave


67. Languages to the world- Jeremy


68. Year CE of the Churban Bayis Sheni- Jeremy



69. Days Menachos grain was planted before Pesach- Dave


70. Interval of years between arrivals of an anti-navigational star- Dave


71. Amos of Heichal (w/o Ulam) in the 2nd Bayis- Dave


72. Amos (+) to a city's Ibur- Shalom


73. Translators of the Septuagint (acc. to 1 version- pardon the pun)- Jeremy


74. Verses in Megillas Esther from Haman's ascension to his hanging)- Alex

food - Can you walk and chew gum at the same time?

Rambam (Hil. Edus 11:4) writes (translation from here):

...base people are disqualified as witnesses by Rabbinic decree. This refers to people who walk through the marketplace eating in the presence of everyone... and the like. The rationale is that they are not concerned with their own shame.

This is cited as the halachah, in practically identical wording, in Shulchan Aruch, Choshen Mishpat 34:18.

Does this also apply to chewing gum or the like?

inorganic chemistry - How can the equilibrium shift, while Kc remains constant?

Consider the following reversible reaction.

$$\ce{Cr2O7^2-(aq) + H2O(l) <=> 2 CrO4^2-(aq) + 2 H+(aq)}$$

What will happen to the position of equilibrium and the value of $K_c$ when more $\ce{H+}$ ions are added at constant temperature?

$$ \begin{array}{lcc} \hline & \text{Position of equilibrium} & \text{Value of}~K_c \\ \hline \text{A.} & \text{shifts to the left} & \text{decreases} \\ \text{B.} & \text{shifts to the right} & \text{increases} \\ \text{C.} & \text{shifts to the right} & \text{does not change} \\ \text{D.} & \text{shifts to the left} & \text{does not change} \\ \hline \end{array} $$

The answer given is D.

I understand that when more $\ce{H+}$ ions are added, the reaction shifts in reverse. So I've understood that this is known as having the equilibrium shift to the left, toward the reactants.

What confuses me is why $K_c$ doesn't change. If the equilibrium shifts to the left, I suppose that must mean more reactants are formed in relation to the products, so $K_c$ would decrease.

But the answer key says that $K_c$ remains unchanged. This is coherent with what I've been taught, but I don't understand how the equilibrium can change yet have $K_c$ remain constant.

I'm just afraid I've got some of the theory mixed up, so I wanted to get some clarity. Could someone explain this please?

Answer

$K_c$ is related to the ratio of reactants to products at equilibrium.

If the reaction is currently at equilibrium, and you add more products then the reaction is now out of equilibrium and the reverse reaction will happen until it is back in equilibrium.

I don't like the wording of "equilibrium shifts to the left" myself, I would say that reverse reactions occurs to restore equilibrium. But $K_c$ doesn't change based on reactants/products concentrations since its the ratio at equilibrium. $K_c$ will normally depend on temperature though.

Based on the options you have, $K_c$ not changing and the reverse reaction occurring, the closest answer would be D. (If you take equilibrium shifting to the left to mean the reaction goes in that direction.)

avot patriarch fathers - If Jews don't eat cheeseburgers, why did Abraham serve a calf with milk?

Genesis 18:8 (JPS):

And he took curd, and milk, and the calf which he had dressed, and set it before them; and he stood by them under the tree, and they did eat.

Looks like Abraham and 3 mysterious visitors don't mind eating mixed milk and calf. If Jews don't eat cheeseburgers, why did Abraham serve a calf with milk?

Answer

I do not have the precise location but I was taught that the Yalkut Yoseph brings down eight answers/considerations to this question. Here are some highlights:

According to Rashi the milk was served first which is entirely permissable. According to the Maharal, Avraham only fulfilled the positive commandments while the Gra brings opinions that he wasn't particular regarding Rabbinic commandments (there is no indication the meat and dairy where cooked together which would constitute a Torah prohibition). And regardless of his own observance, the Shita Mekubetzus points out he thought they were b'nei Noach [non-Jews who are not obligated to separate meat and dairy].

Of course this was before the Torah was given so the question doesn't really begin if one takes a minimalist approach to the question of whether the Avos kept the mitzvos.

words - Cognitive meaning of כפר

What is the cognitive meaning of the root כפר? It's applications (that I know of, feel free to add) are:

• כפיר - lion cub (Shoftim 14:5)


• כפר - village (Shmuel 1 6:18)



• כופר - Replacement (bamidbar 35:31)


• כפרה - Atonement (Shemos 29:33)


• כפר - Cover (Bereishis 6:14)


• כופר - (Rabbinical word) deny

Is there a common denominator? (I left out usages that I see as synonymous, such as bribe [similar to replacement]).

Answer

As @DanF pointed out in the comments, the root meaning appears to be 'to cover', in a literal sense ('to smear') or a metaphorical sense ('to replace', 'to atone'). Gesenius and BDB say as much.

Thus you also have kaporet (Ex. 25:17) which covers the ark, or kopher, the henna plant (Song of Songs 2:14) which is made into a paste and smeared over hands and feet, or kephor, the frost which covers the ground (Job 38:47). Kfar as village probably originates with a cluster of protected or covered dwellings; kfir, they suggest, is a shaggy young lion (i.e. covered with hair or mane).

Cognates of this root with similar meanings are well-attested in Ugaritic, Assyrian, Akkadian, and other languages of the ancient Near East (see, e.g., Lyonnet).

minhag - Why do Hassidim wear hats that simulate what Non-Jewish czars and kings wore?

I heard from a few people that some of the hats that Hassidim wear such as shtreimelach and spodeks mimic the hat styles worn by previous kings and czars. Perhaps, I heard incorrectly, so feel free to provide correct info on where these styles came from.

If it is correct, I am curious as to why they allowed imitating these styles? Two reasons to this question: Isn't this a form of "chukot hagoyim"? Why would they want to mimic the dress style of kings, czars or other leaders that harmed Jews?

etymology - Why is a place that sells さけ a さかや?

Is it known why a さかや normally has a か, rather than a け like in さけ?

Are there many other -や constructions for stores that change the spelling of the word added to?

Answer

(Especially in the ancient times,) there were/are bound morphemes (morphemes that cannot be used in isolation as a word) that end with the vowel a. The a at the end of these morphemes cannot appear at a word boundary. These forms are known as 露出形.

saka- (as in 酒)
ama- (as in 雨)
puna- (as in 船)
ma- (as in 目)

When they are used as the first component of a compound noun, the a-ending is rescued by being attached to the second component:

sakaya (酒屋), sakagura (酒蔵), sakadaru (酒樽), sakamori (酒盛り), sakazuki (盃)
amaoto (雨音), amagasa (雨傘), amagappa (雨合羽), amayadori (雨宿り)

funatsukiba (船着き場), funanori (船乗り), funazumi (船積み), funabashi (船橋), funayoi (船酔い)
mabuta (目蓋), manako (眼)

These morphemes cannot be used in isolation, but there were ways to modify them so that they can be used by themselves. One such way was to attach the vowel i (上代特殊仮名遣い乙類イ) after it, which may be either an epenthetic vowel or a derivational morpheme that derives a noun (this part may be controversial). When such vowel attaches, the a+i sequence became e due to a phonological rule:

a-i → e
saka-i → sake (酒)
ama-i → ame (雨)
puna-i → fune (船)
ma-i → me (目)

These forms derived in this way are called 被覆形.

---

A related question

organic chemistry - What is the preferred IUPAC name of o-toluidine?

Why does o-toluidine have 2-aminomethylbenzene as its IUPAC name?

Why isn't it named as a derivative of amine (like 2-methylaniline)? Aren't amines given a higher priority than alkanes in nomenclature?

See the Priority Chart given on Master Organic Chemistry for reference.

Answer

In principle, your rationale is correct.

Generally, the selection of a preferred parent structure is based on the seniority of classes, which gives priority first to characteristic groups expressed as suffixes. Since o-toluidine (note that this name is no longer recommended) contains only one characteristic group $(\ce{{}-NH2})$, it is named as amine.

According to Subsection P-62.2.1.1.1 of the current version of Nomenclature of Organic Chemistry – IUPAC Recommendations and Preferred Names 2013 (Blue Book), the retained name “aniline” is the preferred IUPAC name (PIN) for the functional parent compound. The systematic name “benzenamine” may be used in general nomenclature.

For the retained name “aniline”, substitution is permitted at any position. Substitution of such functional parent compounds is limited to substituent groups having a lower seniority than that denoted by the (explicitly expressed or implied) suffix of the functional parent compound. Anyway, in this case, this limitation is not relevant since o-toluidine contains only one characteristic group and carbon compounds (rings or chains) have a lower seniority than amines.

Therefore, the PIN for o-toluidine is “2-methylaniline”. The systematic name “2-methylbenzenamine” may be used in general nomenclature.

pronunciation - Inaccurate ruby for 等?

I'm reading a book that contains this sentence:

携帯やパソコンでのメール等｛とう｝のやり取りすらしていない・・・

My first instinct is to read 等 as など, but it has explicitly been given the pronunciation とう via the ruby characters in the text. Of course, とう is a valid reading for 等, but usually only in compound words. Is this a typo, or am I missing some hidden meaning?

This context perfectly fits with the following dictionary definition (デジタル大辞泉), hence my inclination to read it as など:

など【▽等／×抔 】

１ 一例を挙げ、あるいは、いくつか並べたものを総括して示し、それに限らず、ほかにも同種類のものがあるという意を表す。…なんか。「赤や黄―の落ち葉」

Answer

Both readings are valid in this sentence, and they're semantically the same. But とう sounds much more formal.

FWIW, 常用漢字表 only gives the readings of とう and ひと-しい for this kanji. など is widely used, but it's a kind of customary reading.

words - What's the difference between 治す{なおす} and 治る{なおる}?

My dictionary says they are both cure/fix, so I am wondering what the difference is and how to use them?

Is it an active/passive difference, or transitive/intransitive? Or just a subtle nuance? I couldn't find a good example of usage.

I found this question, but it just refers to the different kanji, not the different words.

Thanks

Answer

治す is transitive.

傷を治す
to heal a wound

ほとんどの病気は薬を使わずに治すことができる。
Most ailments can be cured without medicine.

治る is intransitive.

風邪が治った
my cold got better

傷が治らないので、私はまた病院に行った。
My wound did not heal, so I visited the hospital again.

grammar - What is the difference between あっての and とあって?

From what I can tell they both mean "Because of", and the only differences in meaning I can see seem to be very subtle.

あっての:

とあって:

As far as I can tell, the only difference is that あっての proceeds and follows a noun, while とあって can proceed and follow a sentence. Is there some other difference between these?

Answer

Firstly, they are grammatically different. With あっての, both A and B have to be noun phrases, and the result is a noun phrase. With とあって, A can be a noun phrase or a clause, and B has to be a clause, the result being a clause.

Secondly, the focus is different. あっての emphasizes that B could not be without A, whereas this connection is weaker with とあって. With とあって, B tends to be the main point which the speaker is trying to get across, and A is added as extra explanation.

purim torah in jest - PTIJ: What is Nusach Yodeya?

I’m aware that Mi Yodeya has its own Nusach. All I see of it, though, is a special Al Hanissim and other changes on 19 Shevat. Are there any other liturgical changes compared to the more standard nusachos? Where can I find a copy of this Siddur?

---

hashkafah philosophy - Does G-d approve or merely permit human consumption of meat?

Many vegetarians and vegans argue that G-d gave humans permission to eat meat only because of a human failing in abstaining anyway. My takeaway from that argument is that, in light of a more traditional approach I've heard, that after the Flood, all animals owed their very existence to humans and therefore humans were placed atop the food chain, and since humans could not overcome the temptation to remain herbivorous anyway, G-d granted us the right to eat meat. I've also heard that in the days of the Messiah, we will no longer eat meat.

But is that really how are to view this permission? I know a direct parallel cannot be drawn from the fact that G-d asks for animal sacrifice, because we are giving in that case, not taking, and the argument over leather also proves virtually nothing. Further, it makes it even more difficult for us to budget for our own consumption if we have to sacrifice part of our flocks to G-d.

Yet we have certain statements with the force of Halachah behind them (whether we Pasken like them or not), that indicate that eating meat is spiritually desirable. I found a reference to Ramban (online, though I cannot trace the source at the moment) indicating that Kosher meat is good for the soul - of course on the other hand, non-Jews are not restricted to such meat, so there's that. But there is the famous statement that there is no joy without meat and wine, and furthermore a requirement (I'm using that term loosely, although some take it very seriously) to eat meat and fish on Shabbath.

Bottom line, is eating meat a good thing, or is it a concession but better not to if we don't have an overwhelming desire to eat meat? Or is there a middle-ground, that since we have the concession it is something we need not worry about and are free to enjoy?

More food for thought (no pun intended): This answer indicates a necessity to eat meat to distinguish humans from animals (possibly even for the animals' sake as much as the humans'). (If anyone can help with general sourcing, it would be greatly appreciated. I've heard R' Kook strongly encouraged vegetarianism (veganism?). If anyone can provide a source for that, I'd appreciate that as well.)

Answer

These two articles on Chabad.org break it down well, see them for full details and sources : "Judaism and Vegetarianism" and "Chassidic Masters - Meat"

In short:

Originally, Meat was forbidden, since man was unable to elevate it [When a person drinks a glass of water, eats an apple, or slaughters an ox and consumes its meat, these are converted into the stuff of the human body and the energy that drives it. When this person performs a G‑dly deed—a deed that transcends his natural self and brings him closer to G‑d—he elevates the elements he has incorporated into himself, reuniting the sparks of G‑dliness they embody with their source.]. After the flood, man was able to elevate the meat (either because man, the animal, or the world became more refined as a result of the flood - possibly all 3).

Meat is a luxury, while bread is a staple. As such, one should only eat it when he is sure he will have a spiritual advantage over eating vegetation. As our sages tell us that an Am Ha-Aretz should not eat meat (Pesachim 49B) and that one should never eat meat out of hunger, but fill up on bread first (Chulin 84A).

However, if one can properly eat meat, it would be cruel for him not to do so, since he is denying the animal the chance to be spiritually elevated. - see here

---

This covers the Chassidic/Kabalistic approach. The philosophical approach, presented by R' Yosef Albo, is that originally man was told not to kill animals and eat them, since this is a cruel act. The generations preceding the flood mistakenly understood this to mean that animals were equal to man. Therefore, after the flood, G-d commanded man to eat meat, to remind themselves that they were superior to animals, and had a task to fulfill that was not animalistic. When the Torah was given, animals whose meat had negative effects were prohibited.

According to this, eating meat is "necessary, but not desirable".

According to this, Rav Kook said that in the Messianic Era, meat would not be eaten, but "insists that this ideal is not to be assumed as the norm until the coming of Moshiach, when human nature will be completely refined. Until then, he warns, such restrictions may have detrimental effects on man’s moral behavior. (Chazon ha-Tzimchonut veha-Shalom)" - (I didn't look up this source)

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Some more reading material:

meaning - The significance of の in this sentence

I've come across the title of this book:

文句の付けようがないラブコメ

And while i do understand the meaning, I don't quite get the usage of の there. Or, in other words why it is used over を. Any help would be much appreciated.

Answer

文句の付けようがないラブコメ and 文句を付けようがないラブコメ are both fine and mean the same thing.

The former is fine simply because verb-stem + よう works like a noun, just as many other words after a verb forms a noun phrase (e.g. 寿司の食べ方を学ぶ, お金の使い過ぎを反省する). Of course you can use の to connect two nouns.

I'm rather having trouble understanding why the latter is fine at the same time...usually we cannot modify a noun with を. Anyway, this verb-stem + よう also takes を and other adverbial modifiers, too.

• 手の出しようがない。 = 手を出しようがない。
  There's nothing we can do.


• お礼の言いようがありません。 = お礼を言いようがありません。
  
  I can't thank you enough.


• 東京へ(は)行きようがない。
  There's no way I can go to Tokyo (due to an accident, etc).


• 健康に(は)暮らしようがない。
  There's no way I can live healthily.

It seems to me like verb-stem + よう sometimes works like a noun and sometimes like a verb, but I don't know if this is the correct way to explain this. I hope someone will post an authoritative reference.

grammar - What is the nuance when は directly follows a verb in plain form?

It seems like this is a remnant of (or reference to) older forms of Japanese. Is that all there is to it, or does it have special meaning?

Examples from songs:

歌声　笑い声　満ちる大空　目指すは憧れ

(DuDiDuWa*lalala - KOTOKO)

吹きやまぬは残り風 [...]
巡りゆくはこの心

(残り風 - いきものがかり)

And lastly, the same with が:
(At least I suspect that it's not the "but" kind of が. Feels like the subject particle for some reason.)

巡り逢ったが　運の尽き

(刀と鞘 - ALI PROJECT)

Answer

This construct was common in classical Japanese, but now it is archaic or poetic. In classical Japanese, the attributive form of conjugating words can be directly followed by particles which attach to nouns (without inserting の). 目指すは would become 目指すのは in modern Japanese, 吹きやまぬは would become 吹きやまぬのは or 吹きやまないのは, and so on.

sources mekorot - What berachos should be made when Moshiach comes?

I supose shehecheyanu or hatov vehameitiv, but I'm not sure about this. Are there something more specific than that? What are the mekorot dealing with berachos to be made when Moshiach comes?

minhag - Source for Tehillim of your age?

Does anybody know of a source for the minhag to recite daily the perek of tehillim corresponding to your age?

Answer

This is a custom transmitted from the Maggid of Mezritch to the Alter Rebbe of Lubavitch in the name of the Ba'al Shem Tov.

This is recorded in a letter of the Previous Lubavitcher Rebbe, printed in the back of תהלים אהל יוסף יצחק. In this print it is on page 214.

The full letter is printed in Vol 10 of his letters, page 53.

The reason for the custom is cryptically described by the Alter Rebbe here (מאמרי אדה"ז הקצרים page 341), which is somewhat explained by the most recent Lubavitcher Rebbe here.

How to derive Q from r in this filter definition?

I am trying to build a resonance filter with real-time control of both center frequency and Q. I've come across what looks to me like a suitable "recipe" for a second-order IIR filter that might do the job, at http://www.music.mcgill.ca/~gary/307/week2/filters.html (toward the bottom of the page, quoted here with some loss of formatting):

$$y[n] = x[n] - a_1 y[n-1] - a_2 y[n-2]$$

where $a_1 = -2r \cos(2 \pi f_0 T) \\ a_2 = r^2 \\ f_0 = \text{resonant frequency} \\ T = \text{sampling period} $

or more "refined:"

$$y[n] = b_0 x[n] + b_1 x[n-1] + b_2 x[n-2] - a_1 y[n-1] - a_2 y[n-2]$$ where $ b_0 = \frac{1 - r^2}{2} \\ b_1 = 0 \\ b_2 = -b_0 $

The text says of the parameter $r$ that "the closer $r$ is to 1.0, the narrower the bandwidth of the resonance peak." This sounds to me like the definition of $Q$, but I suspect that it's not identical.

My question: What is the relationship between $r$ above and the more usual filter parameter $Q$?

I am just beginning to learn (self-teach) how to build filters, and I am still unclear on some of the concepts. Thanks in advance for any help.

---

See also this question and its answer.

Answer

I'll give you one quick answer (without proofs).

If your mapping from $s$ to $z$ is the Bilinear Transform, then

$$ Q = \frac{\sin(2 \pi f_0 T)}{2} \frac{1 + r^2}{1 - r^2} $$

If it's Impulse Invariant, I think it's

$$ Q = -\frac{\pi f_0 T}{\ln(r)} = -\frac{2 \pi f_0 T}{\ln(r^2)} $$

For high $Q$ and reasonably low $f_0 T$, the two expressions come out nearly equal.

halacha - If a woman proclaims "I am a male", will she become obligated to observe all mitzvos which men are obligated, because of שוייה לנפשה חתיכה דאיסורא?

If a woman proclaims "I am a male, (and I underwent gender-change surgery)", will she become obligated to observe all mitzvos which men are obligated, because of שוייה לנפשה חתיכה דאיסורא - She rendered herself an entity of prohibition?

[Note: If someone finds a source that says that שוייה לנפשה חתיכה דאיסורא only applies to issurim, (prohibitions), then the question can apply to whether she must keep the issurim which men are obligated. ex. not cutting off peyos, not becoming tamei if she's an offspring of a cohen].

parshanut torah comment - Ezekiel 16:4: לֹא הֻמְלַחַתְּ --- what practice does this describe?

Ezekiel 16:4 seems to be describing practices performed on an infant or young child. But, what practice does לֹא הֻמְלַחַתְּ refer to? Do any rabbis explain the meaning?

Answer

Rashi implies that the practice was to salt the infant to strengthen its flesh. (See also Malbim.)

According to Abarbanel, the salt was added in the water to strengthen the infant's body, but also (it seems) for extra hydration.

Apparently, salting newborns was an ancient practice that was also recommended by Soranus of Ephesus. From here:

Soranus recommends that the midwife sprinkle the infant with a moderate amount of "fine and powdery salt, or natron or aphronitre." All these chemicals are mildly astringent and were recommended primarily for their ability to cut through the residue of amniotic fluid, vermix, and placenta on the newborn's skin and also to make the skin less prone to develop rashes; however, astringents would also tend to make the baby's skin dry out and flake or crack. Soranus suggests mixing the salt with honey, olive oil, or the juice of barley, fenugreek, or mallow so the granules are less likely to abrade the baby's delicate skin. The emulsion is to be washed away with warm water and the process repeated a second time.

However, according to Abraham Benisch (quoting Ben-Zeev), the root "מלח" in this case does not mean "salt", but rather "swaddle" or something similar, and this is a parallelism with the next phrase "וְהָחְתֵּל לֹא חֻתָּלְתְּ". Compare to Jer. 38:11: "בְלוֹיֵ מְלָחִים" - "worn rags". (He also compares to "מַלָח" - "sailor/seafarer", but I don't understand the comparison he makes.)

minhag - Why don't we say Tachanun at Mincha on Erev Shabbat or Erev Yom Tov?

It says in the Rambam that there is a custom not to say Tachanun at Mincha on Erev Shabbos and Yom Tov. What is the reason for this custom?

Answer

Taamei HaMinhagim, entry 128, says that we do not say Tachanun on the eve of Shabbat or Yom Tov (and other eves), as a reminder to pray the special prayers in that evening's prayers, or at least as a reminder that the special day that starts that evening.

words - Questions about 背負う

背負う is pronounced せおう, but many dictionaries also list a second pronunciation as しょう.

1. 
   

   I've never heard it pronounced as しょう in practice. In what situations does it have this pronunciation? Is that only an archaic pronunciation, or is it still in use? Is it a regional/dialectical thing? Is one free to pronounce it with either way, unrestricted?

   
   


2. 
   

   せおう (or おう, rather) conjugates as a 五段. Does しょう also conjugate as a 五段?

   
   

• ます形　→　しょいます


• ない形　→　しょわない


• ～て･た形　→　しょって・た


• 命令形　→　しょえ


• 仮定形　→　しょえば


• 可能形　→　しょえる


• 意志形　→　しょおう

Answer

The only difference I perceive is that しょう sounds slightly more "intimate" as if it's a regional dialect. But this doesn't mean せおう is less of everyday language. Probably I feel this way because the pronunciation is a naturally slurred version of せおう (i.e., /seo/ -> /syo/), which is most likely the result of a natural sound shift like 音便.

The tricky thing is that しょう here is not a homonym of しょう as in 賞, 章, and 小. While they look exactly the same in kana, しょう as 背負う does not have the double mora お. It's しょ as one mora plus う as another mora, i.e., it's not the same pronunciation as しょー.

As for its conjugation, it's 五段 as you guessed.

halacha - Deleting files containing G-d's Name / taking the host device into the bathroom

Is there any issue regarding deleting electronic files with G-d's Name in them?

Also, is there any issue with taking such a device into the bathroom?

halacha - Do you have to know kol ha Torah kula?

Is there a requirement for a Jewish man to know the whole Torah (including every gemara, tosafot, Midrasch…) or is it OK to know the Halacha that is relevant to you and then to use the rest of the time to learn those areas in Torah which are interesting for you? If there is such a requirement (to know all the Torah) can someone give me the source for that requirement and also an explanation of why there is a need to learn even those parts which are seemingly not relevant to you?

kanji - Kana causing translation difficulty: 「きれている」

Ok, so I've been having trouble with a passage. It's mostly written in kana, and I can get most of it, but because of the kana, I have no idea what a certain word is. At the beginning of the music video for the Gorillaz music video for Clint Eastwood, it says a line from Dawn of the Dead in Japanese and then in English. Here it is:

すべての死体は死にきれているわけではない。人々はそれらを殺し、そしてまた起きあがって殺す。

In English, of course, it is:

Every dead body that is not exterminated gets up and kills! The people it kills get up and kill!

Of course, I understand the general meaning of the Japanese version, because I have a translation. The last part is easy:

人々はそれらを殺し、そしてまた起きあがって殺す。When people kill them, they get up again and kill.

But the first part I don't understand. I know すべての死体は, and I know 訳ではない, but since it's written in kana, I can't tell at all which きれて is being used. Is it the 〜て form of 切れる? Is it the potential form of 切る? I don't know why you'd be cutting them, and I don't think it's 着れる (because zombies don't spend much time picking out clothes). Secondarily, I'm unsure of the use of 死に here. Is it being きれて'd towards death, or is it 死に as in the other word for death?

Answer

In this context, きれる does not mean "to be cut", but rather attaches to the 連用形 (-i form) of a verb and means "to be able to completely [verb]". cf. the EDICT entry for 切れる:

(suf,v1) (16) to be able to do completely

When used in this sense, きれる is typically written in kana rather than as 切れる.

So, we have 死にきれる (that's the verb 死ぬ, not the noun 死 + particle に) = "to be able to die completely" or, more or less equivalently, "to be completely dead", which maps onto "to be exterminated" pretty well.

parshanut torah comment - 400 Years in Egypt (?)

I know that Samuel David Luzzatto (1800-1865) said that we served all 400 years in Egypt as opposed to just 210. Are then any other "famous" commentators that say this?

grammar - 食べたそうだ vs. 食べそうだ, 静かだそうだ vs. 静かそうだ

I saw this as a comment on this question, Why does そう in 「美味しいそう」 not mean "seem" the way I think it should?「美味しいそう」-not-mean-seem-the-way-i-think-it-should,

and would love to understand the differences.

I am sure I will mangle the translation, so forgive me.

食べたそうだ Looks like he ate it.

食べそうだ Looks like he will eat it.

静かだそうだ I heard that it's quiet.

静かそうだ Seems quiet.

If anyone would be kind enough to explain the differences in meaning and usage, I would greatly appreciate it. I didn't learn how to embed the quoted question, so sorry again for that.

translation - Meaning of 気持ちの持ち方まで問題にしている

I'm having trouble determining the meaning and nuance of this sentence. Can you help me out?

[技術]{ぎじゅつ}といっても、上手か下手かだけではなく、その技術を使う人の気持ちの持ち方まで[問題]{もんだい}にしているのです。

I think the closest I've been able to get so far is…

Even though one may call it a "skill," it's not so much whether one is good or bad at it, but… (how feelings of those who practice the skill are held?)

thermodynamics - Why does equilibrium exist?

I've read an article that equilibrium exists when $G$ (Gibbs free energy) becomes minimum. If formation of products decreases Gibbs free energy, why won't the reaction proceed to completion so that Gibbs energy becomes minimum.

kashrut kosher - Unsupervised milk - there was a treife animal in the herd

I heard in a recent shiur that Dayan Weiss zatzal paskened that an animal that delivered its young via caesarean section is considered a treife. Therefore its milk cannot be drunk. When supervising milking the shomer checks that any such animals are locked away before milking.

How do those those who permit cholov akum put up with this possibility? Is it through bitul?

calendar - 20 Sivan and the inappropriateness of new days of commemoration

The kina (elegy) "Mi yiten roshi mayim" recited on 9 Av was composed in commemoration of the events of the First Crusade as it passed through the Rhineland. It includes the following lines (freely translated):

And because one ought not add a day to the calendar commemorating destruction...
I will instead arouse my cries of "woe!" today [i.e., 9 Av]

One could, one might think, dismiss this viewpoint as one that was not accepted as normative halacha/hashkafa. One could, except that there are those who applied this consideration, in practice, to the Holocaust, saying one should not add a day to the calendar (e.g., Yom Hashoa) commemorating it. (I see this argument attributed to Rabbi Joseph B. Soloveitchik.)

My question is, what do such opinion-holders do with 20 Sivan, which has a history of great rabbis' support, and commemorates post-churban tragedies?

Answer

R' Moshe Feinstein zt"l explains (Igros Moshe, vol. 8, Yoreh De'ah 57:11) that the statement in the kinah is referring to tragedies affecting all of the Jewish people. The Crusaders wanted a wholly Christian world, with no Jews ר"ל (and indeed, they attacked and killed the Jews in Jerusalem as well as in Europe); Hitler's ימ"ש aim was similar. Such calamities are a continuation of the Churban and are included in our mourning for it.

By contrast, he says, Chmielnicki's ימ"ש massacres were a local event, and were not government-sponsored (indeed, the Polish authorities, against whom the Cossacks were revolting, tried to save the Jews where possible). So while it is indeed an outgrowth of galus (in his words, "משום דמאותן החטאים שנתחייבנו בגלות נענשנו גם בזה", "because it is due to the same sins for which we incurred galus that we were punished with this too"), it is something different and deserves its own (local) commemoration.

(R' Moshe doesn't seem to deal with the fact that 20 Sivan had first been established as a fast day several centuries earlier, by Rabbeinu Tam, memorializing the Jews killed al kiddush Hashem following the Blois blood libel of 1171. Perhaps, though, the same logic applies: it occurred in one particular city, and was not sanctioned by the king of France, only by the local baron.)

(Source found in this post.)

digital communications - Deriving SER & BER for 4QAM, 16QAM and 32QAM

Required to find symbol error rate vs $\dfrac{E_b}{N_0}$ for 4QAM, 16QAM & 32QAM. Thought that SER & BER are the same but did my research to find that BER is $\dfrac{1}{\log_2(M)}$ of SER...(could you please confirm this?)

Also found SER for:

4QAM to be: $\text{erfc}\sqrt{\dfrac{E_b}{2N_0}}$

and that of

16QAM to be: $\dfrac{3}{2} \text{erfc}\sqrt{\dfrac{E_b}{10N_0}}$

Are these values correct? Still have problems to find SER for 32QAM...

Hope you can help.

sources mekorot - How high was migdal Bavel?

How high was Migdal (the tower of) Bavel?

From the Chumash we know that the tower was built in a valley which suggests that its purpose was more symbolic than pragmatic. To that effect I am wondering if anything else would stick out as being purely symbolic and more specifically what the height of the tower was. (If the tower was not tall then that would be another suggestion of symbolism.)

halacha - Does Sour Beer Require Certification?

This is my first question ever on this forum, so here it goes!

I am a big beer guy. My wife and I love trying different beers. IPAs are my favorite. My wife's favorite are 'sour beers'. A sour beer is not exactly a flavored beer according to my understanding. It is a type of beer that ferments using wild yeast to get in the mix, which produces its sour flavor (I don't know much about it).

I do know that regular unflavored beer does not require a hechsher. What about sour beers (the unflavored sour beers)?

Thanks!

halacha - May I rely on the halachik leniency of others?

If "Reuven" believes the halacha to be one way and "Shimon" believes it to be more lenient may Reuven rely on Shimon to do something for him based on this leniency?

Here is a 100% fictional practical example to illustrate the concept that I am asking about, please note I am NOT posing this as the actual question, the actual question is what was stated above: Reuven's Rav has given a psak that not using a kli sheini is bishul m'deoraita. Shimon's Rav holds you can use a kli rishon. Can Reuven drink a tea made for him by Shimon?

Answer

From SimchasTorah's excellent answer to Is it permissible to open soda cans on shabbos?

Even someone who does not open cans on Shabbos may use a can that was opened on Shabbos even if they were opened for him (Iggres Moshe: O"C Chelek Daled Siman Kuf Yud Tes Ois Heh) and does not require the person who opened it to drink from it. Non the less he may not ask someone to open it for him(Kuntres Yad Dodi, Harav Dovid Feinstein,pg. 31).

This is not necessarily an answer that applies all across the board, but at least it does indicate that such a principle exists.

Can anyone explain me this MDFT polyphase filter bank?

I found a very interesting piece of code for MDFT polyphase filter bank here. Unfortunately, there doesn't seem to be a paper describing the theory. Does anyone know some reference for the code? I'm especially interested in these 3 topics:

1. 
   

   What are the data in the channels exactly? Are they supposed to be real, imaginary or complex?

   
   



2. 
   

   The code computes only half of the number of bands. Is that due to real-valued signals used?

   
   


3. 
   

   The result of the synthesis stage is build as a channel-wise difference of the outcome of the two synthesis filter banks. Why is it done like that? I can't find any paper describing this idea.

   
   

words - Sentence starting with て?

I was listening to this podcast on Himalaya (Link given below) and I came across this sentence which starts with て, I'm not sure why it starts with て, can anyone please explain this? Also I'm not sure what does ていうのと、あとは means here? Is it some sort of a fixed expression which means "other than that" or something, how do you break this expression down?

​‎ていうのと、あとはやっぱ怒らせないようにっていうのを考えてすごく対応してくれてるって言うのがわかって…

Source: At around 07:22 at http://www.himalaya.com/jp/episode/125679/53455746?Share_from=App&Influencer_uid=1037891&Share_to=Others

Answer

This て is the same as って, the colloquial quotative particle similar to と. The small-tsu is unheard because it's located at the beginning of the sentence. (When written, this っ is usually omitted at the beginning of a sentence, but may be preserved in casual light novels and such.) It may be obvious to you, but this (っ)て refers to what was said in the previous sentence.

っていうのと、…
= ていうのと、…
= というのと、…
= In addition to that, ...

This あとは is like それに, a word used before the last item of a list:

りんご、バナナ、あとはすいか！
An apple, a banana, and (lastly), a watermelon!

But in this case, it's used almost like a filler, and its function is not very different from ていうのと ("...and...", "...to add to that...").

Why does the Lewis definition of acids specify a PAIR of electrons and not a single electron?

The Lewis definition of an acid is: "a compound or ionic species which can accept an electron pair from a donor compound."

Why does it specify a pair of electrons and not just a single electron?

I initially thought maybe covalent bonds require a pair of electrons but it says that is not the case here : https://en.wikipedia.org/wiki/Covalent_bond#One-_and_three-electron_bonds

__

For reference:

Question from textbook : Which of the following species can act as a Lewis acid?

$\ce{NH3}$
$\ce{F-}$
$\ce{H2 O}$
$\ce{NH4+}$
$\ce{BF3}$ (answer)

I thought the answer was $\ce{NH4+}$ as it could accept an electron, but the Lewis definition specifies accepting a pair of electrons.

Thanks.

Answer

It partially has something to do with the history of acid-base definitions. We started with the Arrhenius definition which was based on the generation of $\ce{H+}$ or $\ce{OH-}$ in aqueous solution, and then to the Bronsted-Lowry definition which moved towards acceptance or donation of $\ce{H+}$. Finally came the Lewis Definition which removed $\ce{H+}$ and left us only with electron pairs, to be consistent with the past two definitions. We couldn't just say electrons because that would have included a large class of reactions called redox reactions which are clearly not the same as acid-base.

Now, with respect to your answer to the multiple-choice question:

I thought the answer was $\ce{NH4+}$ as it could accept an electron, but the Lewis definition specifies accepting a pair of electrons.

There are two points that I would like to draw your attention to:

1. You're right in that $\ce{NH4+}$ is an acid (more specifically we call it a conjugate acid), but by the two older definitions.


2. However, $\ce{NH4+}$ cannot accept even one electron in this case. If you draw the Lewis structure, you'll find that although there is a net positive charge, all hydrogens have 2 electrons and the central Nitrogen has eight, fulfilling the octet rule.

blessing - Snuff Bracha or lack thereof

Is there or what is the Bracha on Tobacco Snuff especially now that they come with mint and buble gum flavor (at least in Israel)?

inorganic chemistry - Why is caesium considered the most reactive element and not fluorine?

Some people say caesium is most reactive element. I thought it to be fluorine as it is the element that reacts with almost all elements (except couple of inert gases). But caesium won't react many of the elements in the periodic table, will it?

I just want to know which element is considered most reactive and the basis for such consideration?

halacha - Kashering pot from meat to dairy/parev?

I know I've learned somewhere that you can't kasher a meaty pot for use with dairy (except for Pesach), but I can't find a source for it now. Can anyone provide a source? (The sauce would be a light Alfredo; the source would be somewhere in Yoreh Deah I expect...)

Following on from that, and hopefully to be found in the same source, is my more practical question: can you kasher a pot from meaty to pareve, so that you could cook pasta to be eaten with that yummy Alfredo sauce?

Answer

The Sefer הכשרות by רב יצחק יעקב פוקס explains as follows (chapter 3:5)

• For Sefardim, as long as the item is not ben yomo (has not been used for cooking with dairy/meat) in the last day, it is permissible to change from Dairy to Meat, even lechatchila. Sources: Pri Chadash YD 97:1, Chidah - Machzik Beracha 509:2, Aruch haShulchan YD end of siman 89 and 181:11, Yabia Omer YD 3:4.


• For Ashkenazim the minhag is not to change from one type to the next (Magen Avraham OC 509:11 - since if you get used to changing over, you might make a mistake and kasher a ben yomo pot by mistake) unless it is one of the following circumstances:
  
  
  
  • Sha'at haDechak - Pressing Need/No other choice (i.e.: you need to use the pot for something pressing) (Prim Megadim Eishel Avraham OC 152:13)
  
  
  • Kashering pre-Pesach to get rid of chametz, can switch over from Meat/Dairy (Mishnah Berurah 451:19)
  
  
  • If you will use it for some period of time as a pareve pot before going to the other type (Shu"t Maharsham 2:241, Tzitz Eliezer 9:38)
  
  
  • If it had become treif anyway (ex: it was a milk pot that was accidentally used for meat, when you kasher it you can change it to meat) (Mishnah Berurah 509:25, Shu"t Be'er Moshe 3:105, Maharsham from above)
  
  
  • It hasn't been used for a year+ with its current milk/meat type (Shu"t Maharsham from above)
  
  
  • Received it as a gift and want to change it
  
  
  
  
  


• If you want to kasher using libun you can do so at any time, even for Ashkenazim (Sha'ar haMelech, Hil. Yom Tov, 4:8)

Following from all of that, it seems that if you are Sefardi then as long as the pot is not ben yomo you can kasher to the other type. If you are Ashkenazi then you cant do it unless one of the conditions from above apply (I don't know if wanting yummy alfredo sauce would be considered a pressing need).

gentiles - Can I use a Mikvah if I am not Jewish?

Although I was baptised as a Christian, I feel a strong sense of connection to Judaism and would like to use the Mikvah. I understand that some people believe there is no point/need because I am not Jewish (nor married) and therefore it has no meaning, however, I would still really like to visit one one day. I feel like I need to fill this spiritual void within myself. Is this permissible?

physical chemistry - Why does ice cream make soda fizz?

I've noticed that adding a chunk of ice cream to soda makes the soda fizz slightly near the soda-ice cream interface. I thought it was a physical effect due to the temperature, but adding ice has no effect.

It still can be a physical effect due to solubility, or it may be a chemical effect.

I'd like to know which it is, and the details of the mechanism.

Answer

The reason for this is mainly because of a factor called Nucleation. Although it is not exactly obvious what is the source of the site for the nucleation to occur, what is clear is that there are sites present on ice-cream that are not present on ice alone. The carbon dioxide (CO$_2$) in the drink nucleates and forms bubbles (sometimes even a frothy foam) on the drink.

There are several possibilities some of which are discussed in the excellent answer by Ashu.

I list some of them here starting with what I feel is the most likely.

1. Air in ice-cream


2. Ice crystals in ice-cream


3. Other chemicals found in the ice-cream

torah study - Listening to Music during learning

Is there any "chisaran" (is there something "lacking") in one's fulfillment of the Mitzvah of Talmud Torah if they listen to soft, slow paced, instrumental music (no vocals or lyrics) while learning in order to focus better or drown out background noise?

words - Define the terms used for "types" or "grades" of tefillin

Follow up on this M.Y. question:

The questioner mentioned these grades of tefillin:

• Peshutim


• Mehudarim



• Dakos


• Gassos


• Gassos Prudos

I have heard of some of these terms, but there may be others on this list that I am unaware of, so please edit.

I am uncertain what these terms mean. More curious, why are each of these important, practically? If you can include some history / background to when the grade issue occurred and / or some sources, I appreciate that.

Answer

Tefillin are divided into different categories based on the quality of the leather boxes

• 
  
  

  Tfilin crafted from two separate pieces of leather (which are then glued together) are known as tfilin peshutim, the simplest tfilin. Hasofer says they generally last only three to five years, after which the pieces begin to separate and they lose their required square shape making them invalid for use

  
  


• 
  

  Tfilin made from one very thin piece of leather are called tfilin dakkot, thin tfilin. They are made from a single piece of high grade but thinner leather. The required perfectly square tefillin shape is produced by folding and gluing the leather, or in some cases by stretching the leather over a frame and folding it into shape

  
  


• 
  

  Tfilin formed from one very thick piece of leather are called tfilin gassot, thick tfilin. These are the most durable (and expensive) kind. It is more difficult to make and only became available in the last century or so. The leather is stretched over metal plates and folded and pressed at very high-pressure to form the familiar perfectly square tefillin shape. They will last up to 50 years when properly maintained but are of course more expensive

  
  


• 
  

  Mehudar (as in pshutim mehudarim or dakot mehudarim) refer to more hiddurim (enhancements)

  
  
  


• 
  

  Prudot (separated) refer to the way the four compartments of the shel rosh are separated. Most tefilin gassot are rov prudot, which means they are separate most of the way down, but some glue is applied toward the bottom to help the tefilin keep their shape over time. Tefillin Prudot are completely separated, to meet the stricter opinions. However, note that in some cases they do not retain their shape and have to be reshaped after a few years. Standard tefillin gassot and prudot look almost identical on the outside

  
  


• 
  

  Mikshah echad (one piece): see here for a related answer

  
  

The reason the quality levels are important is simply than the higher-quality will maintain their shape (and kashrut level) much longer. Unless one is on a strict budget, there is no reason today not to buy tfilin gassot. Even economically, it is much cheaper to buy high quality tfilin and keep them 50 years than cheaper ones that need regular fixing/replacement.

The "technology" used to manufacture gassot has only been developed at scale in the last century which is why the tfilin we wear today are of incomparably better quality than those worn by the greatest sages of previous centuries. A wise rav once told me this was because, as we were descending spiritually, maybe we need better religious objects to compensate...

See here, here and here for more sources which I partly leveraged to assemble the definitions above

And here is the best book I found on the intricacies of making tfilin and stam in general. Fascinating reading.

Lost power while using FFT with apodizing mask

Previously I asked this question about FFT artifacts.

The solution that is most easily implemented is using an apodizing mask on the original image, tapering the borders to zero making the image left-right and top-bottom continuous.

The rest of the question is best illustrated with a series of pictures. First, we have the original image:

Now, we apply the cosine-tapered apodizing mask:

Note that we use this mask to do operations in Fourier Space on the second image; to get the power spectrum we will have to use a similar mask again but this is applied to both images so that is not the issue here. (i find it difficult to phrase this properly; please place a comment if you want me to elaborate).

So, now we use a FFT on the second image. In Fourier space we may do things with the image, but to trace our steps and see if the machinery works, we leave it be and just use the inverse-FFT back to real space.

Back in real space, we take the part of the image that was not tapered (so, the inner square) and obtain:

Now, for both the first and the third image I now want to find the power spectrum. In essence, this comes down to (1) using an apodizing mask again, (2) transforming to fourier space once more, and (3) taking the azimuthal average as a function of radius.

As a last subtelty, the power spectrum of the third image is multiplied by a factor $(N_1 / N_3)^2$, where $N_1$ is the number of pixels per side of the first image and $N_3$ the number of pixels per side of the third image. This factor is there to correct for the normalization $1/N$ in the definition of the FFT in numpy.

Doing all this, we obtain the following power spectra:

Clearly, the power spectrum of the third image (in red) has lost power with respect to the power spectrum of the original, first image (in blue). What is the cause of this and can it be compensated for? Or will I have to rely on more elaborate solutions than an apodizing mask (as given here) to not lose this power?

If I am obligated to be drunk all the time, how is Purim different?

We all know the halacha of עִבְדוּ אֶת-יְה-ה בְּשִׂמְחָה (Tehillim 100:2). But the gemara paskens (Pesachim 109a) that since the destruction of the Beis Hamikdash "אין שמחה אלא ביין" ("Joy only comes from wine"). So obviously, one must be drunk whenever serving G-d. Lest one think that there are some times one can be sober, the Mishna (Avos 2:19) tells us "לא עליך כל המלאכה לגמור" (that one may never stop serving G-d).

Clearly, one is always obligated to be drunk.

So how is Purim different?

Answer

Clearly אין שמחה אלא ביין is not talking about joy, since we can experience joy in many ways. Rather, it is referring to שמחה the man. Simcha was a notable drunk who would go to every party that was thrown. The sages realized that if only people would stop serving alcohol, Simcha would not come and be a nuisance.

This is the famous rowdy Simcha who the sages complain after every wedding, long after the party was over:

עוֹד יִשָׁמַע בְּעַרֵי יְהוּדָה וּבְחוּצוֹת יְרוּשָלַיִם

קוֹל שָשוֹן וְקוֹל שִמְחָה קוֹל חָתָן וְקוֹל כָּלָה

[Oy! The party was over five hours ago already, and] we can still hear in the streets of Judah and the avenues of Jerusalem

The shouts of Simcha, Sasson, the groom and the bride!!!

[Haven't they partied late enough?! People have to work the next day!]

There are those who say that Simcha simply was very seriously taking on the mitzvah of rejoicing with the bride, and in honor of that opinion, we bless Sasson, Simcha, and all their friends in all weddings:

ברוך ... אשר ברא ששון ושמחה, חתן וכלה, גילה רינה, דיצה וחדווה, אהבה ואחווה, ושלום ורעות

Blessed are You... Who creates Sasson, Simcha, the groom, the bride, Gilah, Rinah, Ditzah, Chedvah, Ahavah, Achvah, Shalom, and Re'ut.

grammar - When to use するほうがいい instead of したほうがいい in order to mean "Should do"?

So, I was in hello talk writing about how eating ramen everyday might not be healthy:

(I will number the sentences)

1 - ...だから、時々ラーメンを食べたほうがいいね

Then, a native speaker corrected my sentence to:

2 - だから、たまにラーメンを食べるほうがいいね

Someone told me in the past that in order to say "I should..." I had to use the pattern 「た+ほうがいい」 is it wrong?

@Goldbrick also helped me in the chat saying that he'd rather say something like:

3 - だからラーメンを食べるのは時どきだけにしたほうがいい

or

4 - だからラーメンは時どき食べるぐらいにしたほうがいい

He, this time used the したほうがいい pattern instead of するほうがいい. But he couldn't exactly explain why's that...

So when should I use するほうがいい and したほうがいい to mean should?

Thanks in advance!

Answer

You were trying to say you shouldn't eat ramen too frequently, right? Then 時々食べたほうがいい is wrong because it recommends to eat ramen to some extent than nothing.

Adverbs don't determine polarity of a sentence in Japanese unlike English. e.g ほとんど殺した means "killed almost everyone", not "almost killed".

In addition, したほうがいい is an advice for a specific or an actual problem. た form represents that something is concrete. When you are fishing and find some shape, you say いる いる… then, once you confirm it as a fish, you say いた. そういうこと means things like that while そういったこと means things including that. That's how they are different.

In this regard, たまに食べるほうがいい is a little better, if not enough, because it's a criteria for a general problem apart from if you actually do or not.

時々だけにしたほうがいい and 時々食べるくらいにしたほうがいい are fine because either part before したほうがいい stands for refraining from eating too much and したほうがいい recommends to carry out that.

ions - Naming ionic compounds with multiple cations and anions

I have seen complex ionic compounds that have mixed anions and/or mixed cations. For Example I have seen this:

$$\ce{NaKCl2}$$

Also known as Sodium Potassium Chloride. The only information I can find on this is an ion cotransporter for sodium potassium and chloride ions.

Anyway the structure of a single monomer of this would be $\ce{Na+}$ $\ce{Cl-}$ $\ce{K+}$ $\ce{Cl-}$

I have also thought of this as a possibility: $$\ce{Na3ClO}$$

This looks very similar to sodium hypochlorite in terms of its formula but has a different structure. The structure of it would be $\ce{Na+}$ $\ce{Cl-}$ $\ce{Na+}$ $\ce{O^2-}$ $\ce{Na+}$

I know that naming mixed ionic compounds is not easy unlike naming simple ionic compounds(which itself can be hard if you don't know the name of a particular polyatomic ion). But how would I go about naming these mixed ionic compounds?

Answer

I propose you consult the recommendations of the International Union of Applied Chemistry (IUPAC), in particular the Red Book as reference. Obviously, you deviated for a reason from the Hill formula of $\ce{NaKCl2}$ (that were $\ce{Cl2KNa}$) some data bases adhere to.

As already presented in rules IR 4.4.2.1, and IR 4.4.2.2, the order of the elements within the formula may be arranged either by their relative electronegativity (starting by the element of least electronegativity), or by alphanumeric order, respectively. So rules in section IR 5.4 subsequently discriminate between electropositive constituents to be named prior to electronegative ones in the "overall name". In addition (quote):

"The order of citation is alphabetical within each class of constituents (multiplicative prefixes being ignored), except that hydrogen is always cited last among electropositive constituents if actually classified as an electropositive constituent."

The same reference provides numerous examples of application useful to look at, too. Page 76 (of the book, not the pdf) is a good place to start. As in nomenclature of organic compounds, there are instances you want to point the attention not only to the stoichiometric composition of the compound, rather than to different constitutional isomers.

rambam - Why is Maimonides View of Korbanot not Consistent with Messianic Times

Maimonides theorized in his "Guide to the Perplexed" that Hashem did not favor korbanot (animal sacrifices), but allowed them due to the difficulty changing the nature of people. This is in the context of Israel being captive and accustomed to Egyptian ways. The concept of G-d being "reluctant" suggests He did something with hesitation and doubt. How could G-d be in conflict and doubt? Why would G-d "think" Israel couldn't possibly eradicate their pagan-like origins?

I understand that many rabbinic authorities opposed (and continue to do so) Rambam's view on this matter. How did he reconcile this concept with the restoration of the Third Temple during messianic times and the reintroduction of mandatory daily sacrifices? Today, most westerners, including Jews, see animal sacrifices as backwards, kapporos notwithstanding. Hashem didn't foresee this?

calendar - In a leap year, is the extra month Adar I or Adar II?

I'm implementing support for the Hebrew calendar in Noda Time, my date/time library for .NET. I think I'm mostly there aside from text support (although beta testers would be very welcome!) but one aspect still puzzles me.

The Wikipedia Hebrew Calendar entry states that in a leap year, the extra month is inserted before the "regular" Adar:

During leap years Adar I (or Adar Aleph — "first Adar") is added before the regular Adar. Adar I is actually considered to be the extra month, and has 30 days. Adar II (or Adar Bet — "second Adar") is the "real" Adar, and has the usual 29 days. For this reason, holidays such as Purim are observed in Adar II, not Adar I.

So according to this, Adar I is the leap month. However, the Microsoft method of Calendar.IsLeapMonth returns true for year 5502, month 7 - which is Adar II (using civil month numbering instead of ecclesiastical). By my reckoning, it should return true for month 6 instead of month 7.

This is also the way Microsoft handles Adar in Windows Store applications. From CalendarIdentifiers.Hebrew:

During leap years, Adar is replaced by Adar Alef with 30 days and Adar Beit with 29 days. Adar Beit is considered the leap month. The last day of Adar Alef and all the days in Adar Beit are considered leap days.

Currently this doesn't impact my implementation, but I can see that it might in the future - and I'd rather get things right than just follow Microsoft if they've got it wrong. So, who's right in this case? And does it have impact beyond that mentioned in Wikipedia?

Answer

After some much Hebrew googling, it seems as though the rationale is the other way around.

Adar was doubled because it was the last month of the calendar (which started at Nisan with Passover) back then. The decision was to celebrate Purim (and all the other events) in the second Adar as to keep both redemption celebrations close (Purim and Passover). Because of that the first Adar was treated as the "extra" month.

passover - Why do we say only "Morid Hatal" without words "Mashiv haru'ach" before it?

During winter months, we say "You make the wind blow and the rain fall". During the summer, we say only "You make the dew fall." Why don't we include the beginning part about blowing the wind? I noticed that during Tefillat Tal on the 1st day of Pesach, we say the full phrase Mashiv Haru'ach umorid hatal. Why is that the only exception?

Answer

The Aruch Hashulchan OC 114:1 writes that "generally speaking wind brings clouds from which rain falls and therefore we mention them together". Being that wind is not directly associated with the gathering of dew it is not mentioned together. However, Shulchan Aruch OC 114 does state that if one mentions "mashiv haruach" in the summer he does not have to repeat the prayer.

The mention of ruach in Teffilas Tal seems to be in order to fill the meter of the poem.

word choice - What is the difference in nuance between 間違う and 間違え る?

I've heard from a Japanese native speaker friend of mine that both 間違う and 間違える are correct usage, but he wasn't able to explain the difference in nuance between them. Is there a difference, and if so, what is it?

Answer

When we say that someone makes a mistake about something, we can use both 間違う and 間違える and there is no difference in meaning or nuance. For example, 計算を間違えた and 計算を間違った mean the same thing.

[Added remark: As repecmps pointed out in a comment, some people consider this usage of 間違う as incorrect. Someone states that this usage of 間違う was originally incorrect, but I do not know if this statement is true or not.]

When we say that something is in a wrong state, we can only use 間違う. Examples from Daijisen with my English translations:

○ この[手紙]{てがみ}は[住所]{じゅうしょ}が[間違]{まちが}っている。 This letter has an incorrect address on it.

× この手紙は住所が間違えている。

○ [間違]{まちが}った[考]{かんが}え[方]{かた} a wrong way of thinking
× 間違えた考え方

(○ denotes correct examples and × denotes incorrect examples.)

halacha - Air purifier with LED sensor on Shabbat

Would one be allowed to use an air purifier with an LED smell indicator sensor on Shabbat if bringing in odors near the purifier with outside food or other odorous things could or most surely would trigger an LED sensor to go off? The resulting activation of the LED lights would be undesired and the trigger would technically be an indirect delayed activation unlike walking directly in front of a motion LED sensor. The benefit of the purifier would be to control allergy symptoms whereas without it allergies would be worse. Also there is no way to disable the LED lights.

grammar - Why do they use the 連用形 instead of the て form here?

I know that the て form can be used to connect verbs together, like the English "and":

毎日私は食べて寝る。

I eat and sleep every day.

And I know the 連用形 can be used to connect verbs as well, but it kind of combines the meanings of the two verbs, like 飲み込む.

But I am confused by this sentence which appears a lot in TV shows and anime:

この番組はフィクションであり、登場する人物、団体、場所、法律および名称等は実在のものとは一切関係ありません

Why is ある conjugated to 連用形 here? I can understand everything else but this. I have never seen a 連用形 not followed by any other word at the end of a sentence. It is clearly saying that 'This show is a fiction and characters, organization and other stuff is not related to things IRL whatsoever".

Why isn't the て form used here?

この番組はフィクションであって、登場する人物、団体、場所、法律および名称等は実在のものとは一切関係ありません

Can 連用形s be used as て forms, like this?

毎日私は食べ寝る。

Surely not, right?

Answer

Your logic is actually upside down. It's 連用形 that connects clauses, so it's just natural that …食べ、寝る means "eat and sleep". And the point is, te forms are another 連用形 (of 食べつ or 寝つ etc). That's why te forms can connect clauses.

Incidentally, there's no semantic difference between normal 連用形 and te forms in modern grammar.

Academic review of Steinsaltz Gemara

One of the nice aspects of the Steinsaltz Gemaras is that he provides little historical background pieces to figures and objects referenced in the text, as well as linguistic analysis of certain non-Hebrew/Aramaic words. I was wondering how his work is received by academics and if he's considered to be reliable in terms of the history/archaeology/linguistics side of his Shas.

terminology - Grammatically, is a 体言止めの文 a "Japanese sentence"?

In Japanese, a 文【ぶん】 is basically anything which is delimited by periods (マル) or question/exclamation marks. For example, let's say there is a paragraph like this in the middle of the main text of a novel.

夕暮れの川岸を一人で歩く俺。太陽の光を浴びて輝く水面。頬を撫でる風。

Here, we have rather simple 体言止め expressions, which make this paragraph compact yet dramatic. Despite being 体言止め, I believe there are three 文 in this paragraph, simply because there are three periods. If I were to explain this paragraph with grammatical terms, I would say something like this: "This is a paragraph which contains three sentences. Each sentence lacks a main predicate; instead, one long noun phrase forms the entire sentence."

However, on this site, I keep seeing assertions like "Strictly/Grammatically speaking, this is not a sentence in the first place" to explain this pattern. And to my surprise, apparently many users favor this type of explanation. The most recent example is this.

So I thought, "Ah okay, grammatically speaking, sentence in English means something different from 文 in Japanese, and a sentence always needs a main predicate!"

However, I failed to find any credible source to support this. All the serious English articles I've read so far say that a sentence doesn't necessarily have a main predicate. For example, "Hi.", "Yes.", "At three o'clock." and "Two pizzas with cheese crust, please." are English sentences (categorized as minor sentences) simply because they begin with a capital letter and end with a period. Simply put, I found essentially no difference between sentence in English and 文 in Japanese.

So my question is as follows: Is 文 different from sentence? Ordinary English speakers have an idea of sentence which is different from the formal dictionary definition? English speakers who are learning Japanese actually tend to feel there is no sentence in the paragraph above? If yes, how many sentences are there in this article? I feel there are dozens of 文's, and I have never doubted that. On a website where not everyone is an expert, is it unsafe/misleading/unpractical to call the 文 above 'Japanese sentences'?

As far as I can tell, I have never seen a Japanese article which says something like "体言止めの"文"には述語がないので、厳密な文法的には文ではありません".

Answer

When I went to school (K12 in the US during the 70's and early 80's), I was taught that a sentence had to have a subject and a predicate (usually they said verb instead of predicate). But then what exactly are things like "Hello!"

Broadly speaking, what I was taught works very well for formally written, academic, and business English. But often when I write in my journal or even when writing comments on students papers, the style I write in is a rather abbreviated form omitting subjects or occasionally verbs. Yet, what I write is still punctuated, and for want of a better word, I would most likely call them sentences despite the fact that they don't line up with what I was taught.

I think for me what I would call a sentence is something that is recognizable as a complete thought. So in grading a paper, I might write in the margin "poor word choice". I think that expresses a whole thought but I wouldn't be surprised that some would be pedantic enough to argue it's not a proper sentence.

Today I dropped by my local 紀伊国屋 and picked up a copy of マララ. First I was struck by how different it reads in Japanese from English. It made me wonder what the original text was written in. But more to the point, I noticed that many of the sentences in the Japanese translation just weren't really what I would have thought of as sentences. They just seemed to end with out a verb. Sometimes they just ended at what felt like mid-sentence. Yet, the text was perfectly understandable. I knew what the author was saying. And it gave the text a kind informality and colloquial feel to it; I felt a real connection to Malala herself on account of this narrative style. When I went back to an English copy, it suddenly seemed so much more formal and straight laced. As you said, these pseudo-sentences (my word, not yours) in Japanese created a kind of drama of their own that I felt was unfortunately lacking from the pages of the English text.

At any rate, as you can see, despite what I've written above I'm still kind of clinging to your idea of a "strictly speaking" proper sentence--that is, it needs a subject and predicate.

So, in summary, I would say that perhaps 文 and sentence aren't exactly equivalent terms.

Addendum: as I think about this some more, it occurs to me that the difference may be one of orthography too. Odd as it may sound, I thought of this when thinking of lines of Chinese poetry a written in groups of 4 or 5 characters. Yet, they seem to form a unit. Would they be called 文? I haven't studied Chinese so I can't really say. I have studied Sanskrit though, and in something like the Bhagavad Gita the defining unit is the meter of the shloka (verse). At any rate, what I'm suggesting is that the visual (or aural, in the case of Sanskrit) presentation of the text itself is perhaps what originates the meaning of the word 文 or sentence.

Interestingly, my 漢和中辞典 gives one of the meanings of 文 as ことば。また、ことばが集まってまとまった意味を表わすもの。Additionally, the Japanese dictionary on my Mac would seem to define 文 as a unit of meaning. So, I'd say again, this seems to suggest that the two (文 and sentence) are not quite equivalent. 文 seems to be defined semantically whereas sentence seems to be defined grammatically. So there will be a substantial overlap between the two, but certainly not every complete semantical unit will necessary be a so-called complete grammatical structure warranting the name "sentence".