  Anaxagoras was influenced by two strains in early Greek thought. First, there is the tradition of inquiry into nature founded by the Milesians, and carried on by Xenophanes (Mourelatos 2008b) and by Heraclitus (Graham 2008).  The early Milesian scientist-philosophers (Thales, Anaximander, Anaximenes) sought to explain the cosmos and all its phenomena, by appealing to regularities within the cosmic system itself, without reference to extra-natural causes or to the personified gods associated with aspects of nature by traditional Greek religion (Graham 2006, Gregory 2007 and 2013). They based their explanations on the observed regular behavior of the materials that make up the cosmos (see White 2008 on the role of observation and measurement in early Presocratic theories).