by Rabbi Dr. Zev Farber
An analysis of the challenges–both halakhic and social–faced by transgender individuals in the Orthodox Jewish world, with some suggested resolutions.
INTRODUCTION – THE COMPLEX NATURE OF GENDER
One of the most stable identity markers for most people is their gender. We live in a world that divides itself neatly into categories of “male” and “female.” This is true of our language, our bathrooms, our sports teams, etc. For many of us, this reality is perfectly comfortable and intuitive. For those who feel that they were born the wrong sex or who don’t feel comfortable with either of the most common gender identities, this dichotomy can feel isolating.
As challenging as being transgender already is in the larger world, Orthodox Judaism poses some unique challenges. In this essay, I will outline some of these challenges and suggest ways of ameliorating or solving the problems. My goal is to stimulate thought about how to integrate transgender Jews who wish to be part of the Orthodox world, into our shuls and our communities in as seamless a manner as possible.
Clarifying our Terminology
Since discussions of liminal or non-binary sexual identities can get confusing, and since there is no absolute agreement on terminology, I would like to define my terms up front. When discussing a person’s gender identity, at least six things can be meant.
- Genotypic (or Chromosomal) sex – this refers to the person’s genes as per his/her DNA (XX or XY, XXY, etc.)
- Gonadal sex – this refers to the nature of the gonadal tissue (testicular or ovarian)
- Morphological sex – this refers to the appearance of the genitals (penis, vulva, etc.)
- Phenotypic (or Endocrinologic) sex – this refers to the appearance of the person qua his/her secondary sexual characteristics (facial hair, breasts, etc.). In some individuals, these can be mixed.
- Gender presentation – this refers to how the person presents publicly, i.e., the person’s social identity.
- Gender identity – this refers to a person’s innate, psychological identification as a man or woman, which may or may not correspond to the sex assigned to the person at birth. (For some people, gender identity can be hybrid.)
In addition, here are some other terms that would be best to define up front:
- Sex – the classification of a being (plant, animal, or human) based on the type of gonads and chromosomes possessed.
- Gender – the category—male, female, or other—to which a person is assigned by self and/or others.
- Gender expression – the ways in which a person manifests masculinity or femininity, usually as an extension of the person’s gender identity.
- Gender Dysphoria or Gender Identity Disorder (GID) – a strong identification with a sex other than the one assigned to a person at birth. People with GID experience considerable distress because of the conflict between their morphological and/or gonadal sex and their sense of self, and can be divided into two categories.
- Those whose dysphoria is caused by gender expression (masculine-feminine spectrum – dependent on social strictures).
- Those whose dysphoria is caused by gender identity (male-female binary – not dependent on social strictures).
- Transsexual – a transgender person who takes steps to express the characteristics of the opposite sex through hormone treatment and/or surgery.
- Transgender – a) An umbrella term encompassing a wide variety of gender identities; b) a person with GID who lives in a gender role more consistent with their identity than the traditional gender assigned to them at birth
- Intersex – a person born with a reproductive or sexual anatomy that doesn’t fit neatly into the standard binary sexual identity categories of male and female.
I will begin with what seems like the most difficult issue but is, in many ways, the easiest. Some transgender individuals identify so strongly with the opposite gender that their preferred solution is Sex Reassignment Surgery. This operation, which changes a person’s morphological sex, is available for all morphological sexes (male, female, and intersex), although the surgery is simpler for patients born morphologically male than for those born morphologically female.
Male-to Female: The Prohibition of סירוס (Castration)
For morphologically male patients who opt for sex reassignment surgery and wish to become morphologically female, the most obvious halakhic concern is the prohibition of סירוס, castration. The prohibition is derived midrashically from Lev. 22:24, “You shall not offer to the Lord anything [with its testes] bruised or crushed or torn or cut. You shall have no such practices in your own land.” Commenting on this last phrase, the Sifra (“Emor”, par. 7.11) writes:
“You shall not offer” – I only know that they may not offer [castrated animals] how do I know that they cannot perform [the castration]? The verse teaches: “You shall have no such practices.”… How do we know this applies to humans as well? The verse teaches: “among you” – These are the words of ben Ḥakhinai.
This midrash appears also in b. Shabbat 110b, and is codified by Rambam in the Mishneh Torah (Sefer Qedusha, “Hilkhot Issurei Biah”, 16:10) and in the Shulḥan Arukh (Even Ha-Ezer 5:11). Although I have no definitive solution to this problem, I will point out some matters worth considering.
- Rav Eliezer Waldenberg (Tzitz Eliezer 11:78), writes that for a person who cannot have children already, castration would not be prohibited. This brings up two possible extensions.
- Hormone replacement therapy (taking estrogen and testosterone blockers) is an important part of the larger process of transition, and during this process, the male generally becomes chemically castrated. Thus, if the individual undergoing male-to-female transition is already chemically castrated due to hormone therapy, the prohibition of סירוס should no longer apply. In theory, one could argue that this merely throws the prohibition of סירוס back on to the process of taking hormones. Nevertheless, this argument is far from decisive. Taking a single dose of female hormones will not render a morphological male sterile. As there does not appear to be any objective point at which the next dose will cause sterility, it is hard to declare any single act of taking hormones an act of castration. Moreover, whether chemically causing sterility can be defined as an act of סירוס is also unclear.
- Perhaps this could be extended to morphologically male individuals who do not feel psychologically able to consummate heterosexual sex with a woman because, as someone that identifies female, she cannot bring herself to consummate sex in the way a male does. (Rabbis regularly “grant” a heter not to have children to homosexual males for similar reasons.)
- Rav Moshe Feinstein (Iggerot Moshe, EH 4:36) permitted a woman who had a severe nervous condition to have a tubal ligation, even though he considers this to be forbidden (ibid 4:35). Since the need for expression of one’s gender is basic to a person’s identity, it is known that quashing the person’s ability to do so risks the person’s life. An exceedingly high suicide rate exists among those who are prevented from expressing their gender identity and being true to themselves with respect to gender expression. (The case of Leelah Alcorn is one sad example of this trend.) Thus, the Talmudic principle of “’וחי בהם’ – ולא שימות בהם” (‘live with them’ – but do not die because of them)” should be a factor here.
- A stance that pits a transitioning individual against his or her religious community often leads to the forcing of that person out of the Orthodox community . Since transitioning out of a desire to live in their correct gender role can be characterized, at worst, as mumar le-teiavon, and, at least the surgery part, is a transgression that can be violated only once, it might be best to take the position that “let them break one Shabbat so they can keep many more Shabbatot.”
For morphological females who wish to transition to morphological males, the halakhic issues are less daunting. Even following the position that סירוס אשה is prohibited de-oraitta, this would only be relevant if a person were to get a hysterectomy or an oophorectomy, both of which are done for many women to avoid cancer. The procedures that create a synthetic penis and scrotum (metoidioplasty, phalloplasty, and scrotoplasty), however, are not really comparable to castration.
Surgical Transition as Definitive Halakhic Transition
Once the surgery is done, the question becomes, what sex the person is post-surgery, halakhically speaking. Although attempts have been made to define people’s sex in halakha by their genotypic sex, little support for this can be found in the sources. The Talmudic sages knew nothing about genes. The closest thing to a genotypic argument in classical rabbinic literature is the rabbis’ definition of a castrated person as male. This is a very different issue, however, since the castrated person both looks like a male and believes himself to be a male. I do not believe it is sound reasoning to analogize this case to that of a genotypically male person who has sex reassignment surgery, looks totally like a woman (phenotypically and morphologically), and believes herself to be a woman.
In my view, different halakhot lend themselves to a morphological definition, a phenotypic definition, or some combination thereof. Since with post-operative transsexuals, the morphology and the phenotype are the same, I would argue that once a person has a surgical transition, halakhically, his/her sex is the one to which he/she transitioned. The cases in which morphology and phenotype conflict are where complications about definition arise.
OTHER HALAKHIC ISSUES
How should halakha view a person who is phenotypically one sex but morphologically the other? This is a very common reality for transgender individuals who undergo hormone treatment (taking estrogen and testosterone blockers) without surgery–though even that process may chemically castrate the phenotypic male.
This liminal situation interacts with halakhic categories in such a way as to make a number of halakhot difficult to navigate. Three in particular come to mind: sex and marriage, ḥiyuv mitzvot, and seating in a shul with a meḥitza or separate seating.
Although the rabbinic literature does not discuss people who are phenotypically one way and morphologically the other way, it does discuss some types of intersex people, like hermaphrodites (אנדרוגינוס) or people with ambiguous genitalia (טומטום), as well as men who have been castrated or whose penises have been cut off/destroyed.
The existence of intersex people and people with disorders of sexual development makes this category particularly complicated and intricate. For example, people with Klinefelter’s Syndrome—a chromosomal disorder—typically have small testes that do not produce standard levels of testosterone. A shortage of testosterone can lead to delayed or incomplete puberty, breast enlargement (gynecomastia), reduced facial and body hair, and an inability to have biological children (infertility). Some affected individuals also have genital differences including undescended testes (cryptorchidism), the opening of the urethra on the underside of the penis (hypospadias), or an unusually small penis (micropenis). (Klinefelter’s Syndrome is only one example of many similar disorders; more are being uncovered regularly.)
Taking the hermaphrodite as an illustrative example of intersex, the Talmud records a debate about whether the hermaphrodite should be considered a male (m. Yebamot 8:6) or its own category (t. Berakhot 5:15; b. Yebamot 83a). From the fact that these two options are considered, but not the option of female, we can deduce that, for the rabbis, the existence of a penis was a defining factor, but this is only partially acurate since, as noted above, the rabbis did not consider removal of a penis by castration, in cases of a non-intersex male, to be definitive of changing the person’s sex.
Thus, I believe that the best explanation of the rabbinic view–and a good starting point for a modern halakhic treatment of the problem–may be found in the interplay between phenotype, gender identity, and morphology. According to the rabbis, someone who is phenotypically male, identifies as male, but has lost his penis, remains male.
The rabbis do discuss the odd possibility that some castrated men may have an orifice where the penis or scrotum had once been; they even discuss the status of penetrating that orifice, saying that such is not considered sex. These discussions actually strengthen the above point, since they imagine a certain continuity with the man’s past, including his male identity and his male phenotype. In such cases, loss of a penis should not be considered definitive of the person’s gender, but this is very different from cases of sex reassignment surgery.
The distinction between surgically transitioned males and castrated males is illustrative of the problem of how complicated it is to define someone’s sex. How much is it about genitals, how much about phenotype, how much about gender identity, and how much about presentation/gender expression?
Sex and Marriage
When it comes to matters of sex, it is difficult to ignore genitals (for obvious reasons). Again, with post-operative transsexuals, that matter seems simple. If a male transitions to a female and has a vulva and no penis or scrotum, to me it seems counterintuitive to claim that penetration of said person’s vagina by a male should be considered mishkav zakhar (male homosexual sex). The same would apply to a female who transitioned to male penetrating a woman’s vagina with his neopenis—this can hardly be called nashim mesollelot.
I would further argue that even if a man were to have anal sex with a person who surgically transitioned to female, this could not be considered mishkav zachar. The lack of a penis and the creation of the morphological and phenotypic female body makes this person a woman, sexually speaking. Finally, in both of the above cases, I believe qiddushin would be tofsin. In other words, surgically transitioned people are fully transitioned, for the purposes of sex and marriage.
But what about a person who is phenotypically female but morphologically male? Here I believe that for the purposes of sex, it would be very difficult to argue that someone with a penis, even if this person has breasts and other female secondary sexual characteristics, is female halakhically, for the purposes of sex. In other words, anal sex with a phenotypic female/morphologic male would be considered mishkav zachar. Similarly, sex between a female and a morphological female/phenotypic male would be nashim mesolelot. I further believe that qiddushin would not be tofsin between the people described above.
Note: I don’t know what to suggest when it comes to marriages for people who are phenotypically one sex and morphologically another. In this case, the sexual identity of the partners and their social identities are in some tension with each other. Since all these matters are about humans, and the interplay of so many variables differs from one person to the next, perhaps there is no one answer and the issues cannot be solved in the abstract. 
When it comes to ḥiyuv mitzvot, I believe matters are completely different. It is very difficult to imagine that the principle exempting women from many of the positive time-bound commandments (mitzvot assei she-ha-zeman gerama) is based primarily on the existence or absence of a penis. Here I think that sexual/gonadal identity plays a supporting role to social identity. In other words, ḥiyuv mitzvot has to do with the person’s gender role as a male. In such cases, the morphological sex plays a very limited role in comparison with phenotypic sex, gender presentation, and gender identity.
As I understand it, ḥiyuv mitzvot—and I refer here only to the positive time-bound commandments—comes from the social and psychological status of being a Jewish male. Part of this status comes from how others see the person and some comes from how the person sees him- or herself. Thus, since the person’s morphologic sex is only relevant to his or her sexual partner, this should not be the determining factor. Instead, the main factor should be how the community sees the person and how the person sees him- or herself.
Assuming one leaves the problem of continuity aside (i.e. claims of “he was a male/she was a female last week/last year”), it seems clear that someone who looks like one gender and sees him- or herself as that gender, is that gender for social purposes. A morphological female who identifies as male in gender and looks male through a combination of dress, mannerism, and hormone treatment, should be considered male insofar as ḥiyuv mitzvot. It goes without saying that this is certainly true for people who go through sex reassignment surgery.
I will add that even those who are not convinced by the above may wish to factor in the position of Rav Yoel bin Nun that women can accept upon themselves ḥiyuv mitzvot, that the petur is just that – it exempts them from the obligation but does not bar them from being part of it.
The practical ramifications of my position are that Jews who are morphologically female but phenotypically male must wear tefillin, daven three times a day, shake a lulav and etrog, etc. Additionally, they count towards a minyan and may lead devarim she-be-qedusha during services. Since they identify as males, they should be called up as “ben” not “bat” for aliyot, even if this is not strictly accurate in all ways.
The opposite case, male to female transitioning, may be more difficult emotionally for the person undergoing transition in this regard, but works the same way. Morphological males who are phenotypically female and whose gender identity is female are no longer ḥayav in mitzvot assei she-ha-zeman gerama. Thus, they are no longer obligated in tefillin (though I believe they should continue to wear them, as doing so is a mitzvah for women as well as men), and their status in the synagogue should be the same as any other woman. Thus, in virtually all halakhic/Orthodox synagogues, they will not count towards the minyan, they cannot lead devarim she-be-qedusha, and they will not receive aliyot (other than in partnership minyanim, where they should be called up as “bat” and not “ben”).
Meḥitza and Separate Seating
The prayer experience in Orthodox synagogues is gendered. This doesn’t only apply to the issue of who can lead what prayers, but even to the issue of where the average person sits. On what side of the meḥitza does a person sit who is morphologically one sex but phenotypically another? Here I believe that the only answer can be that the person should sit with the gender that he or she presents publicly. This is because the practice of sex segregation for prayer has to do with decorum and distraction. It matters little whether a person is physically/morphologically (assuming one considers the morphological criteria determinative) male or female—a mix up is not going to ruin the synagogue or the prayer service. Rather, what matters is that the service be conducted with decorum and proper social etiquette, which, in meḥitza shuls, includes gender separation.
A Note about Confusion
Some worry that having morphologically female / phenotypic male Jews sit on the men’s side of the meḥitza could cause confusion regarding aliyot, counting towards a minyan, and other kibbudim. I have three responses.
First, I believe that such a person is ḥayav be-mitzvot such that giving them kibbudim would be appropriate anyway. Second, even if the shul or rabbi does not adopt this position, the risk is not greater than when converts or other people who are not halakhically Jewish attend synagogue. This sometimes creates awkward situations but life is complicated and it is better to have an open shul than a closed one. Third, even if mistakes sometimes occur (as occur with gentiles in the synagogue), kavod ha-briyot outweighs any accidental aveirah here, since the stakes in this case are not high, the percentage of transgender individuals is very low, and good people do their best to navigate; nobody and no shul is perfect.
A Note about “Decorum”
It is important to add that when I refer to decorum, I mean it from the stance of the third party observer. In other words, if someone knowing no one in the synagogue were to watch this person come in and say where the person should sit, the observer would point to the section fitting with this person’s phenotypic sex. In other words, a third party observer witnessing a phenotypic male sit down on the men’s side or a phenotypic female sit on the women’s side would not notice anything strange. In fact, if the transgender person in question made the opposite choice, this would look strange to the observer.
I write this because some might argue that since, in the community itself, the person once identified with a different gender, the transition from one identity to the other is disruptive. Undoubtedly, such is the case, but I do not believe that this is a halakhic issue. Celebrities, scandals, and lottery winners are also socially disruptive, but this has little to do with whether, halakhically, they should go to shul. Furthermore, using this definition of “disruptive to decorum” would necessitate that any person who has begun hormone treatment could no longer attend his or her local shul because he or she would, by definition, be disruptive. Either they would look like one gender and sit with the other, or they would sit with whom they looked like but people would know they transitioned. To me, saying that such people cannot attend shul is simply unacceptable and we need to be more accommodating.
Gender Fluidity or Hybridity
All of the above applies to people who navigate their gender dysphoria by transitioning to the gender with which they identify, whether by surgery or hormone therapy. Matters become more complicated with people who identify as bigendered, ambigendered, or gender fluid. Such people generally do not suffer from dysphoria related to gender identity (male-female), but rather from dysphoria related to gender expression (masculine-feminine). Such people do not experience gender as binary and do not feel comfortable conforming to one form of gender expression. Thus, although many are identifiable as phenotypic males or females, in their dress and mannerisms they can express the characteristics of either gender or both, sometimes leaning towards one and sometimes the other in their outer presentation.
This phenomenon is difficult to navigate both when it comes to ḥiyuv mitzvot and insofar as where to sit in a meḥitza or separate-seating synagogue. The reality of the Orthodox Jewish world is that it functions with a male/female gender binary. Thus, I am not sure how to deal with cases in which people’s gender identities do not conform to the standard gender binary assumed by halakha. Although the percentage of such people is low, it is growing quickly and the matter will require more thought and deliberation.
Summary – Primacy of Phenotypic Gender for Most Matters
To summarize my general approach, I believe that the morphological definition of sexual identity is relevant only when it comes to issues of sex and marriage. For all other issues, including ḥiyuv mitzvot, synagogue participation, and where to sit in an Orthodox synagogue with separate seating, the only relevant definition is phenotypic. Thus, unless the rabbi is being requested to perform a wedding or to consult on a matters of a sexual nature, there is no reason for the rabbi to ask transgender people about their genitals. Moreover, since such a question is invasive and crosses the boundaries of tzniut (modesty), the question should not be asked when unnecessary.
CONCLUSION: THE ISSUE OF BLAME
One reason that people react so aggressively to the transgender phenomena is that they see it as an inexplicable choice. The very shocking nature of making fluid that which is so fundamentally solid to most people – their gender identity—brings on insecurity. “What if my own gender identity is not as solid as I thought?” people wonder. “What if my kids follow this new fad and want to have a sex change?” These are thoughts that go through people’s minds and it brings out an aggressive response.
To help combat this reaction, it is important for people to begin to see these phenomena as being outside the person’s control. Instead of feeling frightened by transgender people, it would be more helpful to try to imagine how difficult it would be to feel uncomfortable in your own body, to feel that you are not really you and that your physical sex and your gender identity are discordant. How confusing would that be? Yet this is exactly how many transgender people feel. Shouldn’t this phenomenon make us want to be more compassionate and helpful rather than aggressive and distant?
The 5-ARD Thought Experiment
When thinking about transgender issues, I find the condition of 5-alpha-reductase deficiency-2 (5ARD) to be a helpful analogy. 5-alpha-reductase is an enzyme that converts testosterone to dihydrotestosterone (DHT) in peripheral tissues. The condition is unique to males. DHT has a critical role in male sexual development, and a shortage of this hormone disrupts the formation of the external sex organs before birth.
Individuals with 5-ARD are born with testicles—i.e. their gonadal sex is male—but they usually have female primary sex characteristics. Consequently, they are often raised as girls and develop a female gender identity.
At puberty, individuals often have primary amenorrhoea (they don’t menstruate), and may experience virilisation (development of male secondary sexual characteristics). This may include descending of the testes, enlargement of the clitoris, hirsuitism, and deepening of the voice.
Although most people with 5-ARD identify themselves as females, some may develop a male gender identity coinciding with pubertal virilisation. Others can present with apparent gender dysphoria and transgender behavior.
In the Dominican Republic, in a number of small villages, especially one called Salinas, a majority of 5-ARD patients chose a male identity. The anomaly is sufficiently common there that they have a Spanish term for it, Guevedoche or Guevedoces, meaning, huevo a los doce, “eggs at twelve.” It is also known locally as ‘Machihembras’ (‘first woman, then man’).
The usefulness of this case as a model is that in the cultures where 5-ARD is prevalent, the reality of it is part of life. They know that a number of little girls in their community will inevitably turn into boys when they hit puberty, and that some of them will choose to be boys and others will choose to remain girls. There is no anger or fear of such people in these communities, since the community as a whole has learned to expect it and adapt to it.
What would happen if 5-ARD were a condition common in the Jewish community? Would we help these children with their choices? Would we tell them that once they hit puberty they were no longer allowed in the synagogue? I imagine we would not. If we can begin to think of our transgender children and fellow Jews in a similar way, maybe we can create a more enlightened and empathetic path. Transgender identity, like 5-ARD, is a phenomenon of nature and our job is to help people navigate this complex reality, not to hide from it.
 For more on this, see Kate Bornstein and S. Bear Bergman, Gender Outlaws: The Next Generation (Seal Press, 2010);
 The literature about transgender and halakha is growing exponentially. The most thorough treatment of it to date is, Idan Ben Ephraim, Dor Tahapuchot (Jerusalem, 2004 [Hebrew]).
 After checking a number of medical dictionaries, it seems clear that there is little agreement on the meaning of these terms. Thus, my definitions reflect what I find to be a loose consensus and, more specifically, the way in which I use these terms here.
 וּמָע֤וּךְ וְכָתוּת֙ וְנָת֣וּק וְכָר֔וּת לֹ֥א תַקְרִ֖יבוּ לַֽי-הֹוָ֑ה וּֽבְאַרְצְכֶ֖ם לֹ֥א תַעֲשֽׂוּ:
 לא תקריבו אין לי אלא שלא יקריבו מנין שלא יעשו תלמוד לומר לא תעשו… מנין אף באדם תלמוד לומר ובכם כדברי בן חכינאי.
 This same logic is what brought Rabbi Avraham Weinfeld, in his Lev Avraham (vol. 2, p. 35), to state that smoking cannot be forbidden by halakha outright, since it isn’t any individual puff of a cigarette that causes cancer, but the cumulative effect of long-term smoking. (I am not trying to defend smoking in this note, only to point out that poskim have applied the difference between process and one-time action to other cases of halakha.)
 Although there is also the fact that pregnancy would be life-threatening in her case, it seems that the psychological factor was an independent consideration.
 The principle is found in b. Yoma 85b; b. Sanhedrin 74a; b. Avodah Zarah 27b, 54a.
 For those who believe that even after transition, including surgical transition, a person retains his or her birth gender, this argument would be weakened, since every time the person gets dressed he or she violates כלי גבר / בגד אשה.
 As far as I know, there is no way with current technology to create or graft on an actual penis.
 Metoidioplasty – in this procedure, testosterone is used to enlarge the clitoris. The enlarged clitoris is then disconnected from the labia minora and lowered to the approximate position of the penis by cutting the suspensory ligament. Phalloplasty – in this procedure, tissue from other parts of the body is grafted to form a penis, and an erectile prosthetic is inserted. In both of these procedures, the urethra may be rerouted through the neopenis to allow male style urination through the penis. Scrotoplasty – in this procedure, the labia majora are attached to each other to form an approximation of a scrotum; often two silicon prosthetic testes are placed in the sac to give the scrotum a more authentic look and feel. None of these procedures has any connection with the issur of sirus.
 For more on this, see: http://ghr.nlm.nih.gov/condition/klinefelter-syndrome
 t. Yebamot 10:2; Rambam, Commentary on the Mishna, Yebamot 8:6.
 R. Hananel, quoted in ibn Ezra, Lev. 18:22, states that some men can grow a vagina / have a vagina constructed (כי יש מי שיחדש בגופו כצורת בשר אשה) and that penetrating a male’s vagina would be considered sex, but, as ibn Ezra says, this seems like an inexplicable comment (וזה לא יתכן בתולדה). What exactly is being pictured here is unclear; it may even refer to a case where the man’s penis is still extant.
 For example, I was asked whether an Orthodox Rabbi could perform a halakhic wedding (qiddushin and nissuin) for a pre-operative transsexual woman, who is marrying a biologically female woman. Would this wedding be halakhically valid? Would it be appropriate to do considering how it appears? Such a case brings up the complicated clash between theoretical rules and complex reality.
 The problem of continuity may be more than just social. A person’s gender would fall into the category of a halakhic חזקה. As such, it would require something, like an event or a process, to uproot that חזקה and replace it with another. What would be sufficient to accomplish this—change in morphology? change in phenotypic presentation? change in social presentation?—is an important question that communities will have to think through.
 I admit that I have trouble accepting this line of thought, but I believe it works well as a senif lehaqel combined with my main argument.
 The reverse case poses an interesting problem: A pre-operative transsexual woman (genotypic male) at a transition stage in which she is undergoing electrolysis and laser treatment to remove facial hair and has been on estrogens for enough time that she is starting to show breasts. What would be the dividing line? The problem here is not merely halakhic but emotional/psychological. The average male-to-female transitioning women, if told she counted toward a minyan, would be hurt, as this would be in opposition to the identity she is working to solidify. She might sooner leave the shul, even if she is “the tenth man.”
 At what point the name changes is an interesting problem. Does it change at the beginning of the process? Once hormone therapy commences? After surgery? When does he/she get a new Hebrew name and what happens to the old one? Should both names be used on gittin or in ketubot? These details will need to be worked out over time and hopefully some consensus will emerge.
 In response to an earlier draft, someone asked whether I think we also need to consider the difference between whether other members of the minyan know or not. To what extent is it appropriate to require those who hold different halakhic views to accept ours? Assuming the congregation does not know, one could argue that it is a case of זה נהנה וזה לא חסר, but if they do know, am I arguing that the position that gender can be changed is strong enough that it invalidates the position that it cannot? My answer is that I am arguing my position, since I believe it to be cogent and the one most in line with humanitarian (בין אדם לחבירו) values. Nevertheless, each congregation and rabbi will have to make their own judgments.
 Unfortunately, some people who transition never really develop the look of the gender to which he or she is transitioning. For synagogues navigating such cases, matters will be much more complicated on the “decorum” front, and much sensitivity on all sides will be required.
 One question I have been asked is, what if the synagogue requests that the person take a break from attending during his or her transition period. Transitioning is not an instantaneous change but a process; it is not as if a person is perceived as male one day and female the next, or vice versa. On one hand, I understand this concern, which focuses on the possible disruption to the shul and allowing the community time to digest the situation and giving the congregation some breathing room. If there is another shul in which the transitioning person feels comfortable, this could be a workable solution for some. On the other hand, I have significant concerns with this approach. I tend to be more worried about the transitioning person’s wellbeing than I am about the community. What if there is no other shul? What if this shul is his or her community and its support is emotionally vital? What if the rejection, even temporary, calls the person’s identity, whether it be his or her Jewish identity, religious identity, or social identity, into question. In short, though I understand the desire for space, I would use caution and err on the side of inclusivity.
 Personally, I feel it is more important to try to ensure that Jews, who experience and express gender in a non-binary way, feel comfortable in synagogues than it is to be overly concerned about a small percentage of people with complex gender identities rocking the boat of the majority. Nevertheless, I admit that this situation is more difficult to navigate in Orthodox shuls than the phenomenon of transgender, and will require more thought as the future unfolds.
 A similar cluster of cases among the Simbari of the Eastern Highlands of Papua New Guinea has the local name Kwolu-aatmwol, meaning “female transforming into male.”