In the last lines of the last treatise of Parva naturalia (PN), Aristotle implicitly exhorts the student of nature (phusikos) to end with medical questions. A few lines earlier, he has pointed out that, regarding health and disease, the knowledge of the causes is not only a task for the doctor but also for the phusikos. To explain this, several options may be envisaged, like a deflationist or aporetic reading, or the idea of epistemological subordination of medicine to natural philosophy. This paper aims at showing that a ‘contextual’ and biological interpretation is to be preferred: Aristotle’s exhortation to medicine makes sense in the specific context of the PN, for health and disease are characteristics of living beings, such as the latter are conceived of in the specific context of the PN, where Aristotle deals with states common to body and soul. By doing so, he necessarily deals with their pathological variations as well, i.e. with normal and abnormal states, like health and disease.