Is autogynephilia real? The phenomenon, the construct, the theory

Autogynephilia is a sexual interest in being a woman. Some people argue that autogynephilia isn’t real, often citing Serano’s The Case Against Autogynephilia to support it. I’ve previously counter-argued that autogynephilia is real, but recently I’ve taken a deep dive into psychometric theory that makes me want to revisit the topic in a more nuanced way.

Critics of autogynephilia – or at least, the well-informed critics of autogynephilia – rarely argue that no males find sexual fantasies in which they are women arousing, that transvestic fetishism isn’t a thing, or things like that. These are sufficiently obvious that it would be crazy to deny it. Rather, they argue that these are not sufficient for autogynephilia to be real, but instead that the surrounding theory about autogynephilia is inaccurate, and this makes autogynephilia not real. For instance, quoting Serano:

As others have noted, conflation between the descriptive and theoretical definitions of autogynephilia has lead to a great deal of confusion in the literature on the subject (Wyndzen, 2005). For example, when an author describes an individual as an autogynephilic transsexual, are they simply stating the fact that the individual has experienced “autogynephilic” fantasies in the past? Or are they suggesting that the individual suffers from a paraphilia and became gender dysphoric as a result of such fantasies? To avoid this problem, throughout this article, I will use the term cross-gender arousal to describe sexual arousal that occurs in response to cross-dressing or imagining oneself being or becoming a member of the sex other than the one they were assigned at birth, and I will use the term autogynephilia exclusively to denote the paraphilic model that Blanchard and others have forwarded.

While nobody seriously doubts the existence of cross-gender arousal, there has been considerable debate about autogynephilia. The aspects of the theory that have garnered the most contention are its claims that (a) transsexual women come in two (and only two) subtypes—androphilic and autogynephilic and (b) the assumption of causation—that a “misdirected heterosexual impulse” causes cross-gender arousal, which then subsequently causes gender dysphoria and a desire to transition. While numerous critiques of the theory exist, proponents of autogynephilia have attempted to play down the significance of these critiques on the basis that they were not published in the peer-reviewed literature (Bailey & Triea, 2007; Lawrence, 2007). Here, drawing on these previous critiques, I argue that autogynephilia theory is clearly incorrect. I also discuss how the typology and terminology associated with the theory needlessly sexualizes MtF spectrum people and exacerbates the societal discrimination this group already faces.

One the one hand, I think saying “autogynephilia isn’t real” to attack ideas that are extremely peripheral to the concept of autogynephilia, such as whether there are exactly two types of transsexuals, is extremely misleading and confusing. This isn’t something I’m accusing Serano of doing in this quote, but this is something people who cite her often engage in, and they should stop that.

On the other hand, I can’t entirely reject the point that the validity of a concept inherently depends on the theory surrounding it. Probably the best exposition I’ve read on this is Scott Alexander’s review on Kuhn (probably Kuhn’s writing themselves, as well as later work based on them, are all great places to also read about this). Basically, when doing science, you typically work within a paradigm which dictates the concepts that are relevant to consider, the ways in which things generally work, and the methods of solving questions. There’s no guarantee that concepts that make sense in one paradigm make sense in other paradigms, and generally if someone is working from different school of thought, they might interpret the same object-level observations completely and utterly differently.

So is that the end of the discussion? Either one accepts the entire Blanchardian paradigm, in which case autogynephilia is real, or one is totally justified in including the claim that autogynephilia isn’t real in one’s overall take on things? No incremental progress, just everything or nothing?

I think I have an alternative: Blanchardians usually cite autogynephilic phenomena to defend the concept of autogynephilia, while skeptics usually critique the broader theory of autogynephilia, but inbetween the two extreme ends, we can identify the construct of autogynephilia as covering a sexual interest that explains the phenomenon while being distinct from the theory. Let me explain:

The phenomenon

In my earlier post, I gave lots of examples of the phenomenon of autogynephilia. For instance, I referenced sexual AGP communities (NSFW, hereherehere), trans women reporting autogynephilic sexuality (here, here), autogynephilic men being gender dysphoric (here) and so on.

The phenomenon of autogynephilia is generally identified as being males who engage in sexual fantasies or behaviors based on imagining themselves as women or associating themselves with feminine things. Blanchard observed five kinds of autogynephilia:

  • Anatomic autogynephilia, sexual fantasies and play with having female anatomy.
  • Interpersonal autogynephilia, sexual fantasies and play involving being admired as a woman and having sex with men as a woman.
  • Transvestic autogynephilia, dressing as a woman in sexual contexts.
  • Behavioral autogynephilia, sexual fantasies and play involving behaving as a woman.
  • Physiological autogynephilia, sexual fatnasies and play involving having female physiological functions, such as pregnancy, menstruation, or sitting while peeing.

Realistically, I don’t think these five kinds are a particularly accurate view into how autogynephilia-the-phenomenon works; out of the five top fantasies found in my qualitative survey, only one (“heterosexual sex”) is present in the standard measure of these five types of AGP. So most likely these five kinds of autogynephilia are kinda misleading when it comes to what the phenomenon of autogynephilia really is. But whatever, this isn’t the biggest problem, though it is to some degree a problem, and I will return to that later.

Anyway, the key pattern here is that this is all observational. Notice, for instance, that while in the beginning of the post, I defined autogynephilia as a”sexual interest in being a woman”, but for describing autogynephilia-the-phenomenon, I merely say that it consists of “fantasies and play”, to avoid deeper theoretical conclusions. We observe certain sexual fantasies, we observe certain correlations, we observe lots of things. But “observing” things cannot be a real theory, as it doesn’t tell you how things work; it might be useful for prediction perhaps (“autogynephilia is a symptom of gender dysphoria”), but correlation is not causation. Many different causal theories can be proposed to understand this phenomenon of autogynephilia, and some of the popular causal theories end up treating it as pretty much irrelevant.

The construct

So if autogynephilia-the-phenomenon isn’t sufficient, then what is? The construct of autogynephilia is what makes it start seeming much more relevant, and it’s one of those “hidden assumptions” that might, at least for Blanchardians, be so obvious as to rarely get stated. But I think it’s worth making it explicit. It states that there is a trait, “autogynephilia”, which functions as follows:

  1. It can be understood as a common pathway which is the cause of autogynephilia-the-phenomenon.
  2. It represents a sexual interest, analogous to other sexual interests like gynephilia or fetishism.
  3. Implicitly, in order to represent a sexual interest, the concept of “sexual interest” itself must be coherent and cover the things we wish to place under it.

This is actually really vague. The reason that it is vague lies in point 3; it lacks the definition for what a “sexual interest” is. Here, it is common for Blanchardians to define it as an arousal pattern (see e.g. here for argument), and I agree (with some qualifications, e.g. presumably the arousal is moderated by libido, but the orientation is the effect that exists before the moderation by libido), but for this to make sense, it presupposes an entire theory of sexuality that needs to be explicated. I’d say it goes something like this:

The core of people’s sexuality consists of an “orientation”, which to each possible interest assigns some sort of sexual value. This orientation is reflected in people’s arousal, as they become aroused to the interest in proportion to the sexual value and their libido. Furthermore, also moderated by libido, their orientation creates a sexual motivation to seek out their interest, which affects desires/behaviors/compulsions, though these can also be affected by other factors, such as social norms and pragmatics. The motivation also affects sexual fantasies, but sexual fantasies are likely less influenced by social norms and pragmatics.

This is far from a perfect theory of sexuality. There are likely numerous sexual phenomena that it fails to address; the ways it currently addresses the phenomena are vague and not quantitatively precise; important parts of the theory are dubious (rather than orientation → motivation → fantasy, could one not imagine orientation → fantasy → motivation, where the fantasy functions as a sort of “conditioning”?); and all of the theory is unproven. I will return to that later, but for now, just consider it a hypothetical example of what a solution to (3) might look like.

This leaves (1) and (2). The trouble with them is that they are both tightly coupled to causality, which makes them difficult to evaluate. I have some thoughts on how to show the causality, which I will return to later, but for now, one good starting point might be to evaluate their surface-level plausibility. For instance, Hsu found possibility (1) to be plausible, as when he collected items that covered different types of autogynephilia, he found them all to be correlated, as would be predicted if autogynephilia represents a common cause, and he found his items to be good at distinguishing between ordinary men and men who are involved in autogynephilic groups (in the sense of autogynephilia-the-phenomenon).

But even if one demonstrates that (1) is not obviously wrong and pretends that “not obviously wrong” = strong support, that still leaves (2). To properly validate autogynephilia-the-construct, one would have to show that it represents a sexual interest, which involves first figuring out what “sexual interest” means (as in point (3)), and then show that this plausibly applies to autogynephilia (as in point (2)).

I’m not aware of any time this has been done. Anne Lawrence has sort of played around with it, for instance in Becoming What We Love, or in sections of Men Trapped in Men’s Bodies, but my impression is that her goal here was more to illustrate aspects of autogynephilia, rather than to evaluate whether autogynephilia constitutes a sexual interest.

There are parts of the critiques of autogynephilia that soooooort of go into this, e.g. Julia Serano argues that unlike other sexual interests, autogynephilia tends to go away over time, is present in cis women, tends to lead to emotional attachments and is preceded by ideation in childhood. Certainly if autogynephilia differs from most other sexual interests in all these ways, we should pause and reconsider whether it can really be lumped under the same concept, as (2) asserts. However, I think Serano’s claims are wrong and that they either represent things that she made up without a basis, ideas she got from others who made them up without a basis, or ideas that are based on low-quality observations.

(Serano furthermore distinguishes sexual interests into paraphilias and sexual orientations, which further complicates her argument. Outside of etiology, I doubt this distinction is particularly meaningful (and I’m not even sure it’s meaningful when it comes to etiology), so I don’t think this is super relevant to bring up. However, if you want to know which things exactly she associates with paraphilias vs sexual orientations, you should read her paper.)

Anyway, one could argue that autogynephilia-the-construct as usually presented includes two additional assertions:

  1. Autogynephilia is influenced by gynephilia, being caused by an “inversion” of one’s gynephilia, a process called “erotic target identity inversion”, and is only one out of an entire family of erotic target identity inversions.
  2. There are no other causes of autogynephilia than ETII.

There’s a big critique that can be made of (5), but there’s also something that can be said about (4). So let’s start with (5) and continue to (4) afterwards.

There are three statements that appear to be in conflict. The first is (5), that autogynephilia is always an inversion of gynephilia. The second is (1), that autogynephilia-the-construct is the cause of autogynephilia-the-phenomenon. The third is the observation that some exclusively androphilic and asexual individuals exhibit autogynephilia-the-phenomenon.

The classical solution to these conflicts is developmental competition and meta-attraction (some autogynephiles have in a sense inverted their heterosexuality; they are attracted to being with men, but only as a woman). This is fine as far as it goes, but meta-attraction cannot account for all autogynephiles’ interest in men, and at this point I’m pretty convinced that at least some exclusively androphilic males exhibit autogynephilia-the-phenomenon. (I am not sure about the situation for asexuals/anallosexuals.)

There are two possible solutions to this. One is to drop (5), and say that there exist other forms of autogynephilia, perhaps one associated with androphilia. The other is to drop (1), and say that there are things other than true autogynephilia which can cause phenomena similar to autogynephilia-the-phenomenon. As androphilic AGPs appear to have a similar degree of gender issues to gynephilic AGPs, and as their sexual fantasies look relatively similar (but not entirely identical), I favor dropping (5). But one could also drop (1) instead, and replace it by the assertion that true autogynephilia is only one of the possible causes of autogynephilia-the-phenomenon. These options lead to two genuinely distinct constructs. Dropping (1) leads to what I call “narrowsense autogynephilia”, as it (hopefully! assuming the construct of autogynephilia/ETII is valid) refers to the narrowest, classical notion of autogynephilia, representing an inversion of gynephilic attraction. Meanwhile, dropping (2) leads to what I call “broadsense autogynephilia”, as it refers to autogynephilic phenomena in the broadest sense that is coherent. I expect it to be possible to relate both kinds of autogynephilia in a single model, e.g.:

r/Blanchardianism - Multi-type AGP hypothesis
Diagram relating different kinds of autogynephilia. “AHE” and “meta” here refer to sex as a woman with women and men respectively.

Now, this next part might be considered a bit pedantic, so feel free to skip to the next section as it’s not super important for the overall point of the blog post. But basically, one thing to consider is that (4) is underspecified. This comes into play when one considers other sexual interests that are also proposed to be due to this inversion, such as furries, apotemnophiles, and so on. Namely, these other interests raise the question, is the process that moderates the gynephilia → autogynephilia effect, the same as the process that moderates the other effects? Something akin to this?

Under this hypothesis, there is a variable, “erotic target identity inversions”, which moderates the conversion of any sexual interest (gynephilia, attraction to women; acrotomophilia, attraction to amputees) into an autosexual form.

Or is it more a parallel phenomenon, where each inversion plays out independently across different individuals?

Under this hypothesis, any sexual interest contributes to its autosexual inversion, but the contribution is independent across the interests.

These are genuinely distinct hypotheses, and they have distinct interpretations and predictions. I think Blanchardians tend to favor the first one; for instance, in their autopedophilia study, Hsu and Bailey found that among pedophiles, autopedophilia correlated strongly with autogynephilia, which is the sort of thing you’d expect under the former but not the latter study. However, at least to a degree, this observation could also be explained by the presence of a “general factor of paraphilia”, which appears to exist too. In my attempt to test it, I did not find autogynephiles to have a greater correspondence between the traits they would like to have and the traits that they are attracted to than others, which appears to be in contradiction with the former theory and in support of the latter one.

The theory

And then there’s the theory; while the construct represents the causal claims relevant to defining the construct of autogynephilia, the theory represents all other causal claims related to autogynephilia. The theory implicitly relies on the construct, as one cannot talk about the relationship between autogynephilia and other things if autogynephilia isn’t real, but the construct doesn’t rely on the theory in the same way.

It can be hard to define where the construct ends and the theory starts; for instance, if sexual interests are proposed to be motivating, then that makes autogynephilia’s effect on gender issues part of the construct rather than the theory. There’s some definite distinctions; e.g. the claim that trans women are always either autogynephilic or androphilic and never both would be theory and not construct.

(Uhh… except that the main empirical validation of ETII as a concept comes from observing that androphilic trans women are less likely to be autogynephilic. But this is less about ambiguity and more about the validation of the theory being a bit of a garbage fire.)

But for some things, like AGP being motivating, to some degree it might be more a difference of perspective. For instance, part of the construct definition of AGP is that it works like other sexual interests. Thus, if one keeps a focus on these, e.g. by starting with an idea of how sexuality works, and then testing whether this applies to AGP, that could be considered construct validation. However, if one has something one has observed in AGPs, and one isn’t making any claim of it applying to other sexual interests, then this represents AGP theory. More generally, autogynephilia-the-theory takes autogynephilia-the-construct for granted, and seeks to understand how this relates to other things of interest, whereas autogynephilia-the-construct primarily studies the internal workings of autogynephilia.

Does clinical experience constitute construct validation?

Autogynephilia-the-construct has been “validated” in the sense that there are a number of case studies, clinical experiences, and so on that line up with the idea. I’m not really satisfied with that, though.

As far as I can tell, this sort of clinical experience isn’t particularly reliable. It’s easy to come with several examples of this. The assumption, now known to be false, that autogynephiles cannot be androphilic is a clear example of this. Despite the lack of sound theoretical basis, it has also been asserted that autogynephilic transsexuals have no degree of femininity, which has never been demonstrated and appears contradicted by studies (e.g. this). And of course, as I mentioned earlier, the forms of autogynephilia that have been identified by Blanchard do not well represent the forms that autogynephilia actually takes on in typical fantasies.

One can also consider systematic biases. These sorts of data will tend to skew towards particularly severe, ego-dystonic or otherwise unusual (e.g. in this case, transsexual) cases. These cases are unlikely to give an accurate view of how autogynephilia presents in general. (I constantly have to remind people that the general pattern when studying autogynephiles in a less filtered way is “autogynephiles appear remarkably normal”.) It will also tend to lead to a bias towards more-persistent cases, which if we understand persistence to be part of the construct of sexual interests creates a potential bias.

Clinical experience certainly has a lot of advantages too, though. It allows going into much deeper detail than would be viable in quick standardized surveys, it is generally longitudinal, and it allows some degree of nonsystematic experimentation which may give hints to causality. (Though the previously mentioned biases, as well as factors like regression to the mean, makes this kind of experimentation very dangerous.)

Overall I appreciate the value of clinical experience as a source of anecdotes that can be used to guide theory formation, but I can’t see it as a viable reason to consider theories to be confirmed.

The validation crisis in psychology

I believe debates about whether autogynephilia is real should center on whether autogynephilia-the-construct is real. To understand why, suppose autogynephilia-the-construct isn’t valid. This would mean that apparently autogynephilic phenomena are not motivated by an underlying sexual interest. That would certainly be very strange and hard to imagine, but that is precisely why it is so important; the world must function in a very different way than I imagine if autogynephilia is not a valid construct, and so that implies that I must rethink my beliefs a lot in such a case.

It would probably be helpful to consider various alternative proposals to autogynephilia-the-construct:

  • On page 173 of his book, The Man Who Would Be Queen, Michael Bailey quotes a transvestic fetishist who asserts that the arousal to autogynephilia-the-phenomenon is simply normal gynephilic sexuality, while the motivation to engage in it has nothing to do with sexuality, but is instead simply to “feel feminine”.
  • Serano argues that “autogynephilia” ends up covering multiple distinct phenomena, including reactions to dysphoria and societal sexualization of women, or that they are into it for the sake of novelty. These proposals are very different from how I understand sexual interests to work, and so it would be fair to say that under these sorts of hypotheses, autogynephilia would not be a valid construct (or at least, need not be a valid construct).

(It is worth noting that certain critiques of autogynephilia theory rely on autogynephilia-the-construct being valid. For instance, Nuttbrock and Veale have argued that it arises through the process of “Exotic Becomes Erotic” hypothesized by Bem; but this process is intended to explain how sexual interests develop, and so it is only valid to apply if one understands autogynephilia to be a sexual interest.)

If autogynephilia is not a sexual interest, but instead takes the form of something like the above, then certainly a lot of the Blanchardian theories surrounding autogynephilia look quite silly and often nonsensical. Given what I know, I don’t think this is particularly likely, and instead think that autogynephilia is rather obviously a valid construct.


Here’s the problem: Autogynephilia as a construct has not been validated. Oh sure, symbolic steps towards validation have been performed, such as demonstrating that measures of autogynephilia can discriminate between certain groups. But nobody has taken a powerful construct of sexual interests, and systematically checked that autogynephilia fits under this. As far as I know, there hasn’t even been developed a strong theory of sexual interests that it can be validated against.

Unvalidated, weak theories are hardly unique to Blanchardianism; it’d probably be harder to think of constructs and theories that are validated than ones that are not. Certainly the critics of autogynephilia do not fare any better; concepts like “gender identity”/”gender dysphoria”, “exotic becomes erotic”, “sexualization” and so on are all underprecisified and have only symbolic gestures towards validation. But this isn’t limited to gender topics. Things like the “Big Five” personality traits would probably not fare much better here. It’s not even a problem with psychology research; concepts used by people in everyday life, such as impulsivity, are not validated, and I believe that they are often invalid (this has rarely been demonstrated, but for e.g. impulsivity it appears to be the case). Essentially, this is the state of psychological research:

One “solution” would be to simply disregard psychology as a domain. I don’t think that’s viable, because I want to understand how humans work, and I also don’t think anyone is actually going to do this; instead they are just going to rely on theories that are culturally popular, which is hardly an improvement.

Another solution would be to just keep doing what we are already doing. Combine weak theories, anecdotes, and stray thoughts into vague “predictions”, confirm these predictions and keep on piling up ever bigger questionable theories. Use these vague studies to argue with other people who use other vague studies to contradict you. Keep claiming that your unvalidated constructs are better than their unvalidated constructs. Not particularly appealing, I’d say. It’s probably fine to do this as exploratory research until a clearly defined framework has been established, but one should actually make progress towards having a solid framework over time.

Now, I’m absolutely guilty of this too. My only excuse is that I was just acting like everyone else, but that excuse is hardly enough to justify continuing to act like this, so what am I going to do? I’m going to put much more attention to fundamentals related to validity. New goal: validate that autogynephilia is a sexual interest. And more generally, outside of exploratory research, I’m going to pay much more attention to construct validity.

I’ve talked with other researchers (who are more tightly linked to the scientific establishment) about validity, and they seem to see the concerns too. However, they are more tied up in getting funding and publishing papers, so they tend to address more-immediate questions, rather than focusing on the deeper theory. Which, to be fair, can still be useful, but it seems to me that much more value can be achieved by putting things on solid ground. Since I’m not really addressing the importance of funding or the value/harm of publishing invalid research, this proooobably won’t convince them to change up their method of work. But since I am primarily concerned with understanding how these things work, I’m definitely going to change my method.

The way forward

I used to think proper construct validation was nearly impossible, and so disregarded the question. After all, requiring impossible things would demand that I remain entirely agnostic on how psychology works, which is hardly a workable position. Painfully slow and vague progress in invalid psychology is superior to this.

However, more recently, I’ve been realizing that a large part of it is simply due to the theories being too vague to be meaningful. Obviously you can’t test your theory if you don’t make clear predictions. (Or well, often you can disprove the theory because even vague predictions are precise enough to sometimes be proven wrong.)

In particular, for the case of autogynephilia, the claim is that it is a sexual interest. OK, how do we test that? First, specify what sexual interests are. We’re presumably going to want it to cover factors like arousal, behavior, desire, sexual fantasy, compulsions, proto-sexual childhood ideation, and porn use. Probably more. So build a theory of sexual interests that covers this, by studying sexual interests in general. And then verify that this applies to autogynephilia.

It’s particularly easy when it comes to sexual interests because they are proposed to be a system of several parallel phenomena that all function analogously. I’ve previously attempted to explain how that helps, though that explanation wasn’t very clear, but roughly speaking it goes as follows: It’s easy to come up with many incompatible causal theories that fit any one of them, but it’s unlikely that anything other than reality will fit all of them. Thus, studying sexual interests in general will give us a much better understanding of the causality involved than studying them in isolation will. (Assuming “sexual interest” is a valid construct, but then, if it isn’t then neither is autogynephilia.)

Anyone can “predict” that sexual arousal to the fantasy of being a woman is going to be correlated with wanting to be a woman. This is compatible with autogynephilia-the-construct, but it’s also compatible with there being content overlap (being a woman) between the two items, or by reverse causality, or by monomethod bias, or by all the various other theories that have been proposed. (Confounding can also lead to correlation, but without more specific explanations like content overlap, it doesn’t predict correlation.) That things are positively correlated with each other is called a positive manifold, and this is predicted by lots of theories people come up with. (🤔 Is this a bias in human theory development?) It’s much harder to predict the quantitative strength of this correlation, and few theories would be able to consistently predict this across many variables.

This relies intrinsically on having a strong theory that makes not just qualitative pseudopredictions about the signs of correlations, but instead makes quantitative statements about the exact strengths of causal effects, from which correlations can be derived. Of course, such a theory must to a degree be fit to data to know the coefficients involved; but by being a more universal theory, we can test it on different interests than it is fit to.

(This helps with inferring causality from correlation. However, ideally this should be supplemented by other causal information. Unfortunately, it is super rare that this becomes viable, as causal inference is hard.)

All of this mainly focuses on the validity of structural relationships in the theory. However, this isn’t the only form of validity that is relevant; also relevant is external validity. So far my plan is to assess these different concepts using self-reported surveys, because this is super cheap. However, that kind of data is of very low quality, which may turn out to be an obstacle both for theory inference, and for validity of the inferred theories. I don’t have a great solution for this yet, though I am on the lookout for ones.

In the hope that it can help convince people of the relevance of performing this sort of research, it’s also worth emphasizing what this can give us: directly constructing and validating a model of sexual interests gives a straightforward research program, which if it succeeds will provide powerful arguments on a variety of questions. Pretty much any theory that can be formulated across sexual interests (“porn exposure causes paraphilias”, anyone?) can likely be examined using these methods. And that’s a lot of theories. Perhaps particularly relevant for autogynephilia is the debate about direction of causality; since presumably sexual interests motivate behavior, it’s a reasonable argument for autogynephilia causing gender issues if autogynephilia is a valid construct.


For evaluating whether autogynephilia is real, we should consider whether there is a sexual interest in being a woman that accounts for apparently-autogynephilic phenomena. So far, it has not been demonstrated that a sexual interest in being a woman exists, and so the claim that autogynephilia is real is hardly on solid empirical ground.

This is part of a broad tendency of psychological theories (whether formal and scientific, or informal) to deal with ill-defined and unvalidated concepts. Thus, those that critique autogynephilia for being unproven are not wrong due to their critique being wrong, but instead wrong to raise isolated demands for rigor on just autogynephilia and not everything else too (including on many of the very concepts used to critique autogynephilia).

I personally still believe autogynephilia is real, but I also have some work before me to actually demonstrate that.

Universal laws are causal inference

Edit: It has come to my attention that I did a terrible job of explaining this. I think it’s very important, but the explanation needs to be improved.

OK, the title might be a bit of an exaggeration, but it’s an effective way of summarizing an amazing piece of insight I’ve been thinking about lately.

Suppose you have a causal system. For simplicity, we’ll say that it contains two variables, A and B. Being a causal system means that one of the variables might affect each other. But how can we tell, from pure observation, which variable is the cause, and which is the effect? That should be impossible, right?

For instance, if A and B each have a variance of 1, and their correlation is 0.5, then that can either be due to the rule:

A ~ N(0, 1)
B ~ 0.5 * A + N(0, 0.75)

(which is to say, where B is determined by a combination of A and random noise; noise is denoted by N(µ, σ2), which refers to the normal distribution)

Or it can be due to the rule:

B ~ N(0, 1)
A ~ 0.5 * B + N(0, 0.75)

(where A is determined by a combination of B and random noise…)

These rules give the same observational data, yet are literally opposites. Which poses a problem for causal inference. There are methods of doing causal inference anyway, such as experiments, instrumental variables, and theory, but these are all far too expensive or difficult in many cases. Is there an easier way?

Detour: Some coefficients are unstable across contexts

One of the main cases where you will see this discussed is in genetics. Within genetics, one has what is known as the heritability coefficient, h2, which is generally understood as a quantity that describes how much genetic influence there is on a trait. It is defined to be the fraction of variance caused by genetics.

But by talking about “fraction of variance”, nongenetic factors that increase variance will decrease the heritability. For instance, if you have a number of plants, and you place some of the plants in good conditions and some of the plants in bad conditions, then the growth of the plants will be less heritable than if they were all placed in the same conditions, as there is now extra variance due to the environmental condition. If, on the other hand, the heritability had been unstandardized, if one had talked about just the variance in growth, rather than the fraction of variance in growth, then the condition might not reduce the heritability.

(… or it might. If there are gene-environment interactions or other nonlinearities, as there likely is, then it could very well also affect the heritability. But we will ignore nonlinearities here.)

So one way that standardizing makes coefficients unstable is that they allow downstream conditions to affect the coefficient. To tie this into our previous examples with A and B, even if A causes B at a consistent coefficient of 0.5, the correlation between them is going to vary depending on the noise of B. In the previous example, the causal coefficient matched the correlational coefficient, but if B’s noise had been 0, the correlation coefficient would be 1, while if B’s noise had been 1, the correlation coefficient would be 0.44.

Another way that standardizing makes coefficients unstable is that they introduce a dependence of the upstream conditions. For instance, genetic variance can be lowered in cases of inbreeding, population bottlenecks, avoiding assortative mating, and more. Or in terms of the A/B example previously, if A has lower variance, then the correlation will be lower.

The core asymmetry

Notice an important thing in the above: if A causes B, then variance in A will increase the correlation, while variance in B will decrease the correlation. That’s an asymmetry between A and B! Exactly what is needed for causal inference.

Just to hammer it home, here are covariance matrices for the two causal relations, and two different sizes of variance for A and B each.

Top: Structural equation model diagram which shows the relationships between the variables. eA and eB are the noise terms, with the noise variance being represented by a and b. Bottom: The covariance matrices implied by different values of a and b.

Despite the causal effect being the same in each of the cases, the covariance matrix ends up differing due to the different variances that are introduced. And because of the asymmetry between A and B over the covariance matrices, only this linear causal relationship and not the one in the opposite direction fits the data.

Or to illustrate it in another way, I can generate datasets for each causal direction, for differing variances:

Each circle represents an N=infinity dataset generated by the previously described causal models, with blue dots generated by the A->B model and orange dots generated by the B->A model. The Y coordinate shows the correlation between the two variables in the dataset. The X coordinate shows the relative amount of variance in A and B.

As you can see, while different causal models can overlap observationally, they trace out different curves of possible observational data in the space of covariance structures.

Automagic causal inference

Now this is all well and good, but in reality any dataset is only going to have one noise variance for each of A and B, so how is this useful? This is where the “universal laws” part of the title comes in: if one can make ones theory describe multiple distinct situations, then one could embed the variables A=A'(x), B=B'(x) into a larger family of situations, and require the same theory to apply for each x.

In that case, simply by successfully fitting the theory, as long as the situations are sufficiently distinct, you have much greater confidence in causal validity than you would in a standard case where you are considering only one situation. (It is necessary for the situations to be sufficiently distinct, as otherwise it might fit to all of them through sheer luck.) This is because it’s easy for a wrong theory to accidentally fit a single situation, but hard for it to fit multiple situations.

To give some examples of how that might work:

  • You might wonder if people support some specific political policy because they believe it is beneficial to them. In that case, you could generalize and look at policies in general, examining whether there is support for the general theory that people support policies if they believe they benefit them.
  • You might wonder how people answer a personality item, what influence factors like desirability, memories, actual applicability, etc., have on their response. In that case, you can consider the general theory of how people answer personality items.
  • You might wonder what factors go into creating some kink. Is it porn depicting the kink, traumas surrounding the kink, taboo, etc.? You might also wonder how the kink influences behavior, and in particular whether there is some mediation going on, e.g. does fantasizing increase the likelihood of acting on it? In that case, rather than considering the specific kink, one could consider a general theory of kinks, as this then allows performing causal inference over these questions.
  • And particularly relevant for this blog, you might wonder what makes some people wish to be the opposite sex and what makes some people happy with their sex. And again, here one could embed it into a general theory about how people’s desires to be something specific works.

These are just some beginning examples I’ve thought of, because they are relevant to the topics I’m researching. I would not be surprised if there are analogous examples for other topics, considering how there are so many examples everywhere I look.

(Uhm, though there is one major complication: All of the examples I gave are in the domain of psychology, where measurement error is rampant and correlated, data is ordinal rather than interval/ratio, constructs are dubious and generalizability is unlikely. So it’s pretty relevant to look into how big of a problem these things will be; this is something I’m currently examining in simulations, and I will look at it more in the future.)

What’s interesting to me is that compared to all the other methods of causal inference, this method seem extremely… easy? You don’t need to have a good instrument, you don’t need to carefully look at conditional independences, you just need to look at generalities. And considering how important theory is to do anything practical, you need to look at generalities anyway, so this isn’t necessarily a big restriction. So I feel this is likely a method I will look into more to better understand.