<biography, history of philosophy> presocratic philosopher (c. 585 BCE) who first proposed rational explanation of the natural world. In fragmentary reports from other philosophers, Thales is supposed to have held that "All is water." His Milesian followers commonly disagreed with this simple identification of the archÍ. Recommended Reading: G. S. Kirk and J. E. Raven, The Presocratic Philosophers: A Critical History With a Selection of Texts (Cambridge, 1988); Jonathan Barnes, The Presocratic Philosophers (Routledge, 1982); and The Cambridge Companion to Early Greek Philosophy, ed. by A. A. Long (Cambridge, 1999).
[A Dictionary of Philosophical Terms and Names]
Try this search on OneLook / Google