The Diagnosis of Changing Diseases

In the early modern period, physicians such as Prospero Alpini (1553–1617) demonstrated growing interest in the mutation of symptoms and diseases, as well as in how they succeeded one another or migrated through bodily parts.

In 1627, the Portuguese physician Estêvão Rodrigues de Castro (1559–1637) entered this debate with the publication of the Quae ex quibus (lit. “The things out of which”) in Florence, a ‘quaint title’ that seemingly echoed Hippocratic concerns, but in fact concealed a fully-fledged attempt to explain disease transformation.

While relatively unknown today, the work circulated widely across early modern Europe, being republished in France and Germany and read by physicians such as Werner Rolfinck (1599–1673) and Anne Charles Lorry (1726–1783).

The enduring fortune of the Quae ex quibus was linked to the novelty of its topic, which for the first time focused on the process of disease change and the epistemological tools required to identify it.

This paper will explore how Castro develops a diagnostic grammar of disease change and propagation, granting autonomy to concepts, such as metaptosis (“disease replacement”), epigenesis (“pathological propagation”), and metastasis (“humoral migration”), which had remained peripheral in medical reasoning until the early seventeenth century. In doing so, Castro predates similar inquiries by later authors, especially Giorgio Baglivi (1668–1707).

Ultimately, the Quae ex quibus introduced a major change in the way diagnosis was formulated: in an age of uncertainty, Castro taught physicians to focus their attention not only on the stable and predictable symptoms, traditionally taught in the schools, but also on uncertain dynamics that were difficult to recognise, anticipate, and cure.