Life
Xenophanes in their own century
Xenophanes left Ionia as a young man, probably when the Persians took Colophon, and spent decades reciting his own verse in the Greek cities of Sicily and southern Italy. Fragments of his poems survive in quotation by later writers.
Greek religion had no scripture and no clergy to defend: its authority rested on the poets. Attacking Homer's gods was therefore an attack on the central educational text of the Greek world.
Central ideas
Criticism of the gods of the poets
Ethiopians make their gods dark and snub-nosed and Thracians make theirs red-haired and blue-eyed; if oxen and horses could draw, he says, their gods would look like oxen and horses.
One god, unlike mortals
Against that he sets one god, resembling mortals neither in body nor in thought, who moves all things by the exercise of mind without himself stirring.
The limits of knowledge
Even someone who happened to say exactly how things are would not know it. Our grasp is opinion, though seeking over time makes it better.
Criticism & debate
He wrote as a poet rather than a system builder, and it remains disputed whether his one god is the universe itself, a step towards Parmenides, or a religious claim standing on its own.
Influence
His attack on inherited religion echoes through Greek thought, and his remarks on the limits of what we can know are the earliest sustained Greek treatment of the question.
How to read them
Begin Xenophanes with the tension between criticism of the gods of the poets and one god, unlike mortals. Read the major works slowly enough to notice how biography, public crisis and method shape the argument rather than treating the thinker as a list of doctrines.
If Xenophanes is right about criticism of the gods of the poets, what habit of judgement would have to change first?