Early modern academic physicians followed Galen’s models on many points, including reasoning from signs of diseases back to hidden causes and from causes to signs. Galen’s Art of Medicine (Ars medica, Ars parva, Tegni) famously spurred reflections on the methods of teaching and discovery, which included his categories of analysis, synthesis, and dissolution of the definition. Medieval and early modern physicians at times described analysis as reasoning from effects to causes, and synthesis from causes to effects. Diagnosis often depended on reasoning backward from signs to hidden seats of diseases and causes (analysis), and from causes and organs to signs and symptoms (synthesis). At patients’ bedsides, physicians also moved forward in time, observing disease progression and the effects of therapeutic interventions. From the early 1600s on, physicians at Leiden University followed the Paduan model and used postmortem dissections to confirm or go beyond the diagnoses and prognoses made during daily clinical teaching in the local hospital. These Galenic physicians did not develop radically new medical frameworks, but they did gradually add to the store of pathological and therapeutic knowledge. They based these gradual innovations on their humanist scholarship, as well as on their knowledge of diseases and therapies going forward with living patients, and their inferences from postmortem evidence back to the historical causes of patients’ diseases and deaths. By the mid-1600s, this established pedagogical practice allowed physicians and students pushing new medical theories to generate important new pathological knowledge, notably of consumption (phthisis). By the later 1600s, and into the 1700s, it appears that physicians still reasoned back from signs to hidden anatomical states, using causal principles of natural philosophy, but reserved the terms “analysis” and “synthesis” for mathematics and, especially, chemistry. Although the new Paris medicine, around 1800, explicitly eschewed theoretical systems and causal principles in favor of correlating and counting close descriptions of anatomical and clinical phenomena, the practices of reasoning back from symptoms to impaired organ functions and anatomical states revealed in postmortem dissections appear significantly continuous across the early modern period.