Travel and intellectual exchange across the ancient Indian Ocean world (ca. 100 BCE–600 CE)

The aim of the present chapter is to weave together the seemingly more intangible aspects of the history of intellectual (and religious) exchange with our growing understanding of the history of connectivity and trade across the ancient Indian Ocean. Both the themes and the types of evidence examined by scholars in these respective fields may appear distinctive, at least at first glance. Indeed, it is fair to observe that there is a heavy emphasis on textual study for those working in the areas of ancient philosophy and scriptural exegesis, whereas for the historian of mobility and trade, a much wider range of material is investigated, including archaeological, epigraphic, papyrological, iconographic material and literary texts (of various genres). However, on closer inspection, it is evident that these areas are heavily intertwined. For instance, archaeological studies of sites across mainland and island Southeast Asia have revealed much stronger links with South Asia (and East Asia) from the late centuries BCE than had previously been assumed in earlier Indianization models (Stargardt 2021: 221; Bellina 2022: 459); this has had important implications for our understanding of the processes leading up to the widespread adoption of forms of Buddhism, Vaiṣṇavism and Bhagavatism across Southeast Asia during the first millennium CE. Another example is the value of portable (universal) religions, like Christianity and Buddhism, for merchants and sailors, since they could facilitate a shared sense of belonging and trust, as well as willingness to aid and engage in information sharing among co-religionists (Manguin 2019: 64; Seland 2019: 73). In order to critically examine such entanglements between intellectual and commercial exchange across the ancient Indian Ocean world (ca. 100 BCE to 600 CE) and, in particular, between the Classical Mediterranean and India, several key themes will be considered: travel as a source of (philosophical) wisdom and the importance of autopsy, Indian Ocean islands as the settings for philosophical utopias in Graeco-Roman literature, and the potential for material evidence to be studied as proxies for the movement of religious and philosophical ideas. However, before addressing these themes it is worth providing some contextual discussion of the motives for travel and the practicalities involved.