The argument of this paper is based primarily on a close reading of several Hippocratic texts;1 parallels with Chinese traditional medicine are adduced. Study of Greek medicine is usually situated in the context of western medical history. However, it is evident that the vascular anatomy envisaged in the Hippocratic Corpus is not at all coincident with our known post-Harveian model; it here becomes apparent that it is coincident rather with Chinese patterns. The supposed working and actual treatment of the body are fundamental concerns of doctors in any society, but different suppositions have been made, and different practices followed, in different ages and different places. When the evidence from Greek and Chinese traditions is pared down to parallel analysis under the broad heads of physiology (nature of the body), pathology (nature of disease) and surgery (nature of treatment), remarkable common essentials and shared anatomical presuppositions are seen to emerge. Parallel analysis of a specialist field, ophthalmology, reveals common elements also. There are obvious limitations and difficulties in essaying an approach which is neither clearly synchronic nor firmly diachronic. Once similarities between two modes of thought have been isolated, quid sequitur? Similarities in practice can readily be explained by common human physiology: doctors of different societies at different times might treat similar afflictions in a similar way because they separately have discovered an effective treatment on an empirical pragmatic basis. Similarities in theory are less readily explicable. In general, there are two ways to account for these: firstly, contacts and interactions between peoples, with consequent influence, whether one-way in one of two directions, or two-way in both; or secondly, independent appearance of similar modes of thought. Some tentative conclusions—and questions—are put forward in the final section. The possibility that remote contacts may have left vestigial traces in the earliest evidence for both Greek and Chinese medical traditions is aired. And finally, it is suggested that western medicine may be less firmly rooted in the Greek past than historians and practitioners alike tend to believe. The nature of the evidence, complex on both sides, requires a brief preliminary discussion. The Hippocratic Corpus, as we know it, comprises some sixty to seventy treatises. There is a growing scholarly consensus that the quest, initiated in antiquity and continued until the middle of the twentieth century, for “genuine” Hippocratic works among them is futile: they are so disparate in expression and content that, at best, broad groupings of related works can be established.2 It is now recognized too that other medical writing from the classical period (fifth and fourth centuries bc), not generally regarded as “Hippocratic”, may once have had comparable status. A collection of evidence for the survival and usage of the Corpus in antiquity exposes the fragility of our post-publication and post-renaissance Hippocratic construct.3 It is unsurprising that, with regard to the particular questions addressed here, the views presented in the Corpus, itself heterogeneous, are not entirely homogeneous. For Chinese medicine there is no documentary evidence, and very little evidence of any kind, before early second century bc. That is not to say that medicine begins in this period, merely that evidence before the Han period cannot be safely reconstructed: in view of the disturbed political conditions, this is unsurprising. The first published translation of the earlier part of the Nei Ching (Neijing) remains useful. Its content is the basis of exposition in many secondary works on Chinese medicine.4 Although the text of this monumental Classic of internal medicine is difficult and uncertain and its date disputed, the general content, in many respects already clear, can be supplemented and reconstructed from later recensions and interpretations, such as that of the Ming period; also by medical texts found in tombs of the second century bc (the Mawangdui tombs). There are evident hazards in comparing the amorphous Hippocratic material with the still more amorphous material from China.5 Nevertheless, despite variations in the Greek evidence, certain common elements in theory and practice can be isolated; and despite the paucity of early evidence from China, an abundance of later evidence compensates.