Xenophanes was from Colophon in Ionia, but traveled around Greece as a peripatetic poet. He was born around 580 BCE and died around 480 BCE. He was one of the first philosophers of religion, and is distinguished from previous religious thinkers because his thoughts were based on reason and argument rather than mysticism, revelation, or mythopoeticism. Although he thought that inquiry helps us make better discoveries, he asserted that with nature and with the gods all we ever have is belief, never knowledge. He believed that there must either be one god or one god who is unquestionably a superior god. But he believed that this god is unknowable to mankind, and is dissimilar to mankind in shape and thought. He criticized the common tendency to see gods as we are, like when the Ethiopians make their gods snub nosed and dark skinned, and the Thracians make their gods red-haired and blue-eyed, and he even thought that if horses could draw they would draw their gods to look like horses. Xenophanes's god is eternal, homogeneous, sees as a whole, hears as a whole, and thinks as a whole, and never moves but does everything by thought. It appears that Xenophanes may have been a pantheist. He was the teacher of Parmenides and may be responsible for important aspects of the latter's philosophy, in that Xenophanes argued that everything that exists is one and changeless and entirely heterogeneous and this is the one god. He believed that the elements making up all beings are either just Earth or Earth and Water. He stated that the Earth extends down forever beneath us. He thought that the ocean produces clouds, rivers, rain, and wind; that the sea is salty because it has many things mixed in it; and that rainbows are a type of cloud. There are an infinite number of suns and moons, and our sun comes into existence each day from an amassing collection of small sparks. He also made the argument that because there are fossilized sea creatures on land, at one or more times in the past the earth was covered with water, and that the Earth would recurrently be covered by water in the future.