The False Binary Between Biology and Behavior

PPP Continuing Commentary

This article comments on the following previously published article: Moncrieff, J., “ It Was the Brain Tumor That Done It!” Szasz and Wittgenstein on the Importance of Distinguishing Disease from Behavior and Implications for the Nature of Mental Disorder. Philosophy, Psychiatry, & Psychology, 27 (2), 169–181.

Joanna Moncrieff’s philosophical views on the nature of mental illness (Moncrieff, 2020) represent in many ways the enduring legacy of Thomas Szasz in philosophy of psychiatry. She articulates a defense of Szaszian thinking about disease, with connections to Wittgenstein’s philosophy, that is probably as compelling a defense as a contemporary student of philosophy is likely to find. However, Moncrieff’s eloquent arguments contain significant conceptual problems, and I will try to explain some major points of contention in this commentary.

Moncrieff, following Szasz, categorizes behaviors as either resulting from a bodily process or as self-directed behavior. In my view this distinction is a typical example of a false binary (or the logical fallacy of the excluded middle). False binaries distill a complex set of options into two mutually exclusive options. Neurological processes and intentional, self-directed behaviors are not mutually exclusive (Bolton & Hill, 2004). There is a complex relationship between behaviors and underlying biological processes (which can include diseases). Furthermore, many psychological states and psychiatric conditions cannot adequately be described using the terms “self-directed” or “behavior.” States of mood and perceptual experiences of auditory hallucinations are strictly speaking neither “behavior” nor “self-directed”. This mischaracterization of complex psychological states and psychiatric conditions as “self-directed behaviors” creates a lot of confusion and helps nudge Moncrieff to arrive at invalid conclusions.

According to Moncrieff, Wittgenstein’s philosophy illustrates that the ‘mental’ cannot be equated with the biological since mental attributes are inherently entwined with public behavior. I agree that mental cannot be equated with the biological, however, that nonetheless leaves open a myriad of ways in which the biological relates to the mental. Consider sexual desire. Sexual desire is conscious, psychologically meaningful, and it is usually, if not always, directed at an object. While sexual desire is “mental,” it is influenced by biological factors such as the production of various hormones. Sexual desire cannot be “equated with” hormonal signaling, but hormonal signaling plays an important role, and changes in hormonal signaling underlie as well as influence the experience of sexual desire. We do not choose to experience sexual desire; we can exert some control over it, but it is not entirely under our control, and we have little control over the object of our desires.

Moncrieff sees mental disorders as aspects of character and self-directed behaviors, but she acknowledges that they are not always rational or fully controllable, and for that reason they may not necessarily be accompanied by moral responsibility. Stating that self-directed behaviors are not always fully controllable and may not be associated with moral responsibility seems to me to be a self-defeating effort considering that one of the reasons Moncrieff is against viewing mental disorders as diseases is because it contradicts the sense of agency. It is also odd that Moncrieff allows “aspects of character” to be have a complex relationship with agency, yet she denies the same complex relationship to behaviors caused by disease processes such as brain tumors. I would argue that the relationship between behaviors and brain tumors can be just as complex.

Moncrieff uses the examples of epileptic fits, blinking, and brain tumor causing pedophilic behavior to argue that biological causation trumps other explanations of behavior. It is a mistake to lump epileptic fits with complex behavior such as pedophilia arising in the context of a brain tumor. An epileptic fit by-passes the conscious decision-making processes of our mind-brain. Neurological reflexes such as blinking also involve no conscious decision-making. Pedophilic behavior, however, is much more complicated because it does involve conscious awareness and decision-making.

What does it mean for complex human behavior—characterized by awareness, intention, and conscious decision—to be caused by a brain tumor? How exactly does a brain tumor result in pedophilic behavior? It...