The Fall 2016 edition of The New Atlantis: A Journal of Technology and Society consists of a careful analytical review of the scientific literature available across various disciplines on the topic of human sexuality and gender. The authors, Lawrence S. Mayer and Paul R. McHugh, are senior scholars with impeccable credentials and qualifications to undertake a major report such as this. The report takes a careful look at the literature and decides in an informed and straightforward way what the available science does and does not say—or, more precisely, what conclusions current science does or does not justify—about these important aspects of our humanity.

Any reader will note that the report takes up some issues that lie close to the heart of contemporary discourse about sexual orientation and gender identity. Cynical critics will probably try to dismiss it based on supposed ulterior motives. However, if the topics covered by the report are, in fact, areas where science has been co-opted by politics, and where scientists, and laymen, have overreached in making conclusions and invoking the authority of science, then these are precisely the areas where sound, careful, rigorous scientific response is necessary. As Mayer and McHugh write:

When the research touches on controversial themes, it is particularly important to be clear about precisely what science has and has not shown. For complex, complicated questions concerning the nature of human sexuality, there exists at best provisional scientific consensus; much remains unknown, as sexuality is an immensely complex part of human life that defies our attempts at defining all its aspects and studying them with precision.

Good scientists follow the data where they lead. They are constantly open to alternatives and remain mindful of scientific and intellectual rigor. To dismiss this scientific report as merely political is to misread it—not only cynically but unscientifically. The report, with its substantial body of analyses and findings, stands on its own ground, and it certainly provides sufficient material for study and response by serious investigators. Even serious cynics have a responsibility to deal with the data.

Key Findings

It’s worth reading the report in full. Here I begin by summarizing four of its principal findings. Based on the data presented by hundreds of peer-reviewed scientific studies, the report concludes:

1. Claims that sexual orientation is immutably determined by biology are not supported by scientific evidence. 2. Claims that gender identity is somehow fixed and innate, yet is also independent of biological sex, are likewise not supported by scientific evidence. 3. Since the great majority of children who experience some gender-atypical thoughts do not continue to do so after adolescence, encouraging such children to become transgender or seek invasive and sometimes drastic and irreversible medical procedures is not supported by scientific evidence. 4. The finding that non-heterosexual and transgender individuals have higher rates of mental health problems is supported by scientific evidence, while the common attribution of such findings to the effects of social stigma or stress as the only or primary cause is not supported by scientific data.

As the authors note, some questions relevant to sexuality and gender have lent themselves more readily to empirical study than others. One such finding, which is of great concern to the authors, is that sexual minorities “show higher rates of depression, anxiety, substance abuse, and suicide compared to the general population.” The most common explanation, known as the “social stress model,” is that such outcomes are caused by the stigmatization and discrimination experienced by these individuals. Although this theory has great cultural currency, Mayer and McHugh conclude that “science has not shown that these factors alone account for the entirety, or even a majority of the health disparity between non-heterosexual and transgender subpopulations and the general population.”

With respect to questions of gender identification and biological sex, the authors conclude:

In reviewing the scientific literature, we find that almost nothing is well understood when we seek biological explanations for what causes some individuals to state that their gender does not match their biological sex.

Nevertheless, the authors note, “despite scientific uncertainty, drastic interventions are prescribed and delivered to patients.” They find it particularly troubling “when the patients receiving these interventions are children.” Based on the lack of data on long-term consequences of these interventions, Mayer and McHugh strongly recommend caution when it comes to practices such as gender reassignment surgery and hormone therapy.

Science Requires Critical, Rigorous Self-Examination

In their conclusion, the authors call for more and better-quality scientific research in all areas taken up in the report. They also reiterate the value of the sort of scientific endeavor of which the report is a good example. They are aware that their report provides both critique and challenge to the “born that way” paradigm for understanding sexuality. As they point out, such a careful critique and challenge “enables us to ask important questions about sexuality, sexual behaviors, gender, and individual and social goods in a different light.” At present, however, there is undeniably “a great chasm between much of the public discourse and what science has shown.”

The overall message of the report is that very few claims and very little of contemporary “knowledge” in the area of human sexuality and gender are actually supported by strong scientific evidence. I must say that I was not surprised by this conclusion. I learned in my graduate training more than three decades ago that social relevance can be intoxicating for social scientists; even a whiff of the possibility of social relevance can be irresistible. Unfortunately, the social science disciplines have never been given to fits of critical and rigorous self-examination. This new report suggests that the same may be true of some practitioners of the hard sciences as well.

There are three principal reasons I was not surprised at the findings and conclusions of the Special Report. These are also principal reasons why this is a very important report that deserves careful study and broad dissemination. The first reason comes from a rather well-documented contemporary controversy within the social sciences: the need for replication. The other two reasons are more philosophical, although I am not a philosopher by training: the relationship of the physical with the non-physical and the question of biological determinism. These issues are related to the nature of science itself—and to the question of what it means to be a human being.

The Replication Crisis

In recent years, both academic and clinical psychologists have begun to give much anxious attention to “The Replication Crisis.” Put simply, researchers have discovered that the successful replication rate for social scientific studies is alarmingly low. This is troubling, given that reproducibility has always been a touchstone for scientific rigor. Over and over, Mayer and McHugh note that careful examination of the scientific evidence shows inconsistent findings, failures to replicate data, and conflicting results.

The great historian of psychology, Sigmund Koch, observed as early as 1959 that psychology was unique among the sciences in that it essentially chose its methods before settling on its questions. Given that its methods were adopted from the natural sciences and its questions from the human world, the “fit” between the detached methodology of the social sciences and phenomena as subtle, engaging, and deeply meaningful as sexual feelings and behaviors is simply not easy or obvious.

What is clear is this: the commonly cited conclusions regarding the biological causality and fixedness of sexual orientation, and the social stress hypothesis, have been too facile. It is telling that those areas where the scientific research is clearest and most consistent are those areas that most straightforwardly lend themselves to empirical study, for example, in relationships between sexual practices and measurable medical and psychological health issues. I agree with Mayer and McHugh that much more and much better research needs to be conducted in this important area.

Can Physical Things Cause Non-Physical Phenomena?

The fundamental reason these findings are not surprising is that there is not—nor has there ever been—any explanation for how such subtle, complex, socially relevant, purposeful psychological phenomena (non-physical things) could possibly arise from or originate in the body (a physical thing). Likewise, I am not aware of any instance in which a particular, meaningful, purposive bit of behavior has been shown to be produced by a particular physical biological substance or structure. What is usually demonstrated is that some sort of abnormality of the nervous system or brain impedes what would otherwise be a particular, meaningful, purposive behavior. But prevention is not causality, and the logic simply does not hold that if a damaged physical structure impedes a particular behavior, then a healthy physical structure can be assumed to produce the corresponding healthy behavior. Scientific evidence also shows that when I am doing something, so is my brain; however, demonstrating that a healthy brain is always involved in my meaningful purposive behaviors does not constitute evidence that those behaviors (or feelings) are produced by the brain. It is true that when the brain stops working, thinking stops. It is also true that when the liver and lungs stop working, thinking stops. We think with our brains; our brains do not think.

Therefore, it is not surprising that science has not provided evidence that sexual orientation or gender identity have a biological cause and fixed nature. There is simply no conceptual or philosophical reason to expect that that should or could be the case. In this light, it is clear why the report finds that scientific methods have been most effective in those areas where the data are clearly empirical and there are no claims of causality between two separate ontological realms—the psychological and the physical. The clearest positive scientific findings in the report deal with the relationship between phenomena related to sexually relevant feelings and behaviors, and clinically relevant mental-health feelings and behaviors.

The presumption that any aspect of meaningful human sexuality—above the level of simple biological functionality—should have its origin in the biological substrate comes from a metaphysical commitment, not from science. Such a metaphysical commitment to some form of reductive or emergent materialist naturalism is not required by science qua science, which only requires order in the universe and the capacity within the scientist for observing and making sense of that order. The naturalist assumption is thus not necessary for science, but it is a foundational assumption of scientism.

Biological Determinism Makes Life Meaningless

The report shows that there is little scientific evidence supporting the view of sexuality and gender that has come to pervade our culture. I would even go so far as to say that this scientifically unsupported view is intellectually incoherent. It renders sexuality and gender essentially meaningless. To the extent that sexual motivation, attraction, and behavior are biologically fixed, they lose their meaning. If my sexual motivation, attraction, and purpose are immutably determined by my biology, then so must be my ability to do anything about them, including to act on them or refrain from acting. This would have troubling consequences when it comes to issues such as rape or sexual assault. For why should we believe that an orientation or an attraction might be biologically determined while an inclination, desire, or action is not?

And if orientation, attraction, desire, and even action are biologically given, on what basis could we say that pleasure is not? If sexual phenomena are fixed by biology, when it comes to feeling enjoyment or love during sex, I am not really joyful or in love—at least not in the sense that joy or love is anything more than a biochemical reaction.

In the end, trying to understand sexual phenomena in terms of biological determination renders them meaningless. Meaning requires an agentive participation in the phenomena. Our agentive nature operates at the heart of human sexuality, much as it operates at the heart of other meaningful human experience. At times, this takes the form of a consciously deliberated rational choice that brings moral meaning and purpose to our lives. At other times, our agentive being will manifest itself more as a “giving ourselves over to,” or a “taking on” of meaningful possibilities. In such choices and actions, we find our humanity.

Clearly, common cultural beliefs about sexuality and gender are wrapped up in a problematic, incoherent, and internally inconsistent understanding of what it means to be a human being. On the basis of Mayer and McHugh’s report, we may fairly conclude that a fundamental reexamination of how we think about sexuality and gender is in order. Perhaps we ought to reexamine our vision of the human person as well.

Mayer and McHugh’s new report is an important document. It clarifies the state of scientific knowledge in a most important and culturally weighty area. It is thorough, unbiased, and straightforward. I hope the report is read, cited, and used both for its clarifying and its heuristic value.