On several occasions in the course of an argument the Hippocratic treatises recommend corroborative procedures to their readers that closely resemble what we would call an empirical ‘experiment’. Airs, Waters, Places, for example, offers two in succession in ch. 8, which discusses rain water and water from snow. In the case of rain water, the author asserts that the sun draws up the finest parts and leaves behind the heavier, and that the same process holds for the human body, namely that the sun draws up the lightest part of its humors. A proof (tekmêrion) is offered in the form of an experiment: one can sit in the sun wearing a cloak and observe that the parts that are exposed to the sun dry up the sweat, while the parts that remain shaded remain sweaty. The case of snow water (where the claim is that water from thawed snow or ice always deteriorates in quantity and quality) involves an experiment of measuring the quantity of the water before and after freezing. All such cases present attempts to confirm (expressed in a variety of ways in Greek) hypotheses about the processes of the natural world inferred by observation but difficult or impossible confirm by the senses alone. We cannot quite explain what happens to water when it’s thawed, e.g., but we can see the consequence of thawing over and over in a familiar context, and we can eventually feel comfortable that that consequence will be predictable and stable.
I see in this intellectual procedure significant connections with earlier attempts in poetry to concretize and stabilize the world of invisible or impenetrable processes by analogizing them to the familiar and perceptible. Similes are the most prominent example of such thinking, which serve, as G. E. R Lloyd put it in Polarity and Analogy (190), ‘to describe…or apprehend the unknown by likening it to something known or familiar.’ I would like to argue for a more specific linkage between poetic similes such as we find in abundance in Homer and the discourse of early scientific and medical experimentation. The Hippocratic recommendations to confirm something by experiment, I will argue, are methodologicaly aligned with the kind of analogizing we find in the Homeric simile. Just as Homeric similes strive to explain intangible things such as emotions and psychological states by mapping them on to permanent, predictable and known qualities of familiar phenomena (Lloyd 184), so, as I’ll argue, early scientific experimentation can be seen as similarly striving to explain often imperceptible natural processes by working with stable and familiar phenomena. One can see this process at work in the first Hippocratic example above, paraphrasing: ‘the sun draws up the finer parts of water in the world, just as one can see water disappearing from one’s cloak on a sunny day.’ No one would dispute that sweat will disappear in the sun every single time anyone is in that situation, and from this predictability one can recur to the original questions about rain water, drawing inferences to support one’s original hypotheses, now with more confidence on the strength of a testable, tangible analogy.
Experimentation: Querying the Body in Ancient Medicine