(Disclaimer in advance: I'm not really going to deal with medieval and Early Modern criminal psychology here, just because I haven't read much about it outside the context of self-murder and suicide. I'm also not going to touch on werewolves, but I really wish I could touch on werewolves.)
In the medieval and Early Modern world, there was a not inconsiderable amount of effort and ink devoted to what we might now describe as psychological and psychiatric concerns -- emotion, mood, behavior, reason, mental illness. There were also protocols that might be identified as the ancestors to modern therapy. But none of this necessarily looked a great deal like modern self-help, modern psychiatric diagnosis and treatment, or modern therapy. Let's unpack that first cluster of stuff, then.
First, we might want to talk about what one might call normative upkeep -- all that stuff my therapist says it's totally normal for people who are otherwise mentally well to need from therapy and self-help -- or tools for people with emotional difficulties but no pressing disorders or abnormal behaviors. In the medieval and Early Modern world, it's nearly impossible to disentangle spirituality from psychology -- the whole massive industry of spiritual advice could be broadly considered to fall into this category of self-help texts, with the aim of bringing the reader into closer compliance with a particular model of spiritual virtue or at least to help the reader to align themselves within a set of parameters for good spiritual function. There are non-pathological reasons why an individual might struggle, after all, including severe misfortune, disappointment, and one's own impending mortality.
Consolation narratives were written by and for the grieving -- the most famous and influential might be Boethius' 6th century Consolatio Philosophiae/Consolation of Philosophy, which remained a tremendously popular text through the end of the Middle Ages. In Boethius' case, the work finds its author imprisoned and awaiting execution; through the work and its rhetorical presentation of concepts the author's predicament and also the reader's is rendered philosophically intelligible and imparted with meaning. This might not be "grief" in the modern sense of having lost a loved one, but the Consolatio and its imitators model how to bear misfortune and difficulty even unto death while maintaining one's personal stability and integrity of self. These unfortunate events (as well as more conventional grief events like the death of a loved one) are mitigated by being given philosophical meaning. Later Renaissance-era dialogues and texts addressed sorrowing individuals' sentiments and emotions, providing reassurance through appeals to religious and philosophical order and educating the hearer on how to master their emotions of sadness and grief. Other texts might promote the mastery of other passions such as anger.
In addition to amateur advice from friends and family members, an individual (man or woman) might seek spiritual consolation from a text such as a didactic poem or from an individual such as a confessor or a spiritual director. For princely men and women, this might accordingly be a confessor who specialized in advising princes. There was no equivalent in medieval and Early Modern professions that really maps tidily onto the modern role of the therapist, but in terms of individuals who had a sustained professional relationship of intimate spiritual counsel to an individual, these professional princely confessors are more akin to the modern therapist than general parish confessors might be. (Of course, your local confessor still provided intimate spiritual counsel, but he'd be juggling a much bigger workload. There's an abundance of books and texts prescribing protocols of questioning for regular confessors and penances to be assigned, but penitentials and confessors' manuals don't necessarily paint an unbiased image of medieval realities.) Royal confessors provided counsel to the men and women they attended with an expectation of strict privacy -- in the Early Modern period, the counsel element steps up beyond the counsel expected of any local priest assigned to a royal residence's chapel to a more intimate role. Given the role of Early Modern princes in politics, however, this rarely stayed restricted to private concerns. The confessor to a prince might have tremendous (even worrying) access to the prince's political decision-making. In theory, the confessor was in a unique position to speak the truth to the prince without hope of personal advancement; in reality, this wasn't necessarily the case. The princely confessor at best was a combination of a therapist-equivalent and a political advisor; at his worst, he was an interferer, severely overreaching his therapeutic bounds.
(Side note: In the 16th and 17th centuries, Jesuits were frequently confessors to princes and subsequently were the targets of frequent accusations of betraying their responsibility for the prince's spiritual good in order to serve the interests of their Order. The Society of Jesus took the risks of these accusations to heart and issued decrees as early as 1593 discouraging Jesuit confessors from participating in political decision-making or using their position to advance the Society or their own personal interests, even familial interests, but it didn't take, and the specter of avaricious Jesuit confessors tricking and manipulating the individuals in their confidences into materially benefiting their Society remained a stock aspect of anti-Jesuit sentiments through the 19th century. That is all!)
Of course, the biggest difference between a therapist and a personal confessor is the religious function of the latter -- it is in a therapist's interest to make their patient well, while it's in the confessor's interest to make their parishioners good. The confessor is more a doctor of the conscience than of the mind. The medieval and Early Modern idea of mental wellness is hard to disentangle from the idea of personal goodness, but unwellness isn't necessarily synonymous with wickedness -- what of disordered mood, and of individuals largely in possession of their rational faculties who are nevertheless troubled by persistent sorrow? What about mental illness, not just moral culpability?
There's an abundant religious vocabulary to describe actions and qualities we might now associate with the realm of the psychological first and foremost -- spiritual sloth, acedia, demonic possession, and so on. But what about a medical vocabulary, or at least a partially medical one? Melancholia's origins are often described in humoral terms -- even its name derives from the humoral system and suggests an overabundance of black bile is producing the cognitive and emotional symptoms a melancholic person suffers from. Melancholia and its sister condition, hypochondria (not the "hypochondria" of modern psychiatry or idiomatic use) both are physical conditions rooted in the body and its organs. They are both products of internal imbalance, and they can be remedied both with physical treatments to restore the balance of the internal body and with religious treatments to restore the sufferer to a state of spiritual ease. Medieval doctors found precedents for melancholic illness in medical writing from antiquity and documented its symptoms as they saw them in their own medical texts. The 13th century Dominican author Vincent of Beauvais describes telltale symptoms of melancholia in his Speculum Maius, for instance, as does the 11th century physician Constantinus Africanus, arguing that melancholia is an ailment affecting both body and soul -- but Constantinus is a physician, not a cleric, and in his translations of Arabic-language texts he centers on physical cures, not psychological ones. Information regarding mental disturbance and its treatment was indeed deemed valuable by scholarly recorders -- these medieval models of melancholia overlap with spiritual conditions like sloth or acedia, but they are not in opposition to them.
One patient's account of melancholia is that of King Duarte of Portugal (1391-1438), as compiled in his text "O Leal Conselheiro" (The Loyal Counsellor)-- he lists melancholy, "an illness of the melancholic humor", among the causes of sadness but deals with it on its own terms as a chronic but partially treatable condition. He even gives pharmaceutical recommendations… at least by 14th century standards of pharmaceutical ingredients:
[Duarte] recommends fasting as usual and the taking of “common pills” whenever the sadness arises. A recipe in his commonplace book explains that these contain saffron, myrrh and açefar (aloes?); fennel, lemon, bugloss, or rose waters, or white wine; and mastic and spurge. Half a silver spoonful was to be taken with cold water or wine or honey depending on the individual’s [humoral] complexion. (McCleery)
(I regret that I in no way have a reading knowledge of 14th century Portuguese, but if you do, you can read a transcription of the original text here as part of the University of Wisconsin's Ibero-American Electronic Text Series. The author covers a lot of territory besides melancholy -- the text is more of a compilation of assorted writings than a purpose-written treatise.)
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