This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Nothing Pyrrho himself wrote survives, and by his own choice he appears to have written nothing at all, so everything attributed to him personally passes through at least one later hand before it reaches any surviving text. His student Timon of Phlius is the earliest source, transmitting Pyrrho's teaching and reputation in verse composed after Pyrrho's own lifetime, already shaped by a student's own literary purposes rather than a transcript. The fuller philosophical system that later carries Pyrrho's name, worked out by Aenesidemus centuries afterward and preserved most completely in the writings of Sextus Empiricus, is a systematic body of skeptical argument Pyrrho himself never composed.
Scholars who study the movement therefore distinguish, with real difficulty, between what the historical Pyrrho of Elis is likely to have held and lived by, chiefly the practice of suspending judgment in pursuit of tranquility, and the elaborate argued case for that suspension that Pyrrhonism became only generations later. How much of the developed skeptical system reflects Pyrrho's own thought, as opposed to a name later thinkers attached to a movement they built largely themselves, remains an open question in the scholarship on ancient skepticism, unresolved because the one kind of evidence that could settle it, Pyrrho's own words, was never set down to begin with.
The gap between the man and the movement bearing his name is not an incidental complication in Pyrrho's case, it is close to the whole of what makes him difficult to study at all.