Cratylus the Heraclitean Testimonies in Greek

The Testimonies is a modern scholarly designation for the collection of ancient reports concerning the Athenian philosopher Cratylus, an extreme follower of Heraclitus active in the late 5th century BCE. No writings by Cratylus himself survive, and our knowledge of his thought is derived entirely from later testimonia preserved primarily in the works of Aristotle and Plato. The standard collection of evidence comprises a handful of key passages that document his philosophical positions. These testimonia focus on Cratylus’s radical development of Heraclitean doctrine, particularly his assertion that all things are in a state of constant and universal flux. From this premise, he concluded that stable knowledge and even reliable reference through language were impossible. This profound skepticism regarding language’s capacity to represent a changing reality is famously illustrated by Aristotle’s report that Cratylus ultimately refused to speak, communicating only by moving his finger. The principal sources for these ideas are Aristotle’s Metaphysics, Plato’s dialogue Cratylus—which bears his name and features him as a character—and a brief biographical note in Diogenes Laertius’s Lives of the Eminent Philosophers. Cratylus’s historical significance lies chiefly in his influence on Plato. Aristotle records that Plato was familiar with Cratylus’s doctrines from his youth, and this engagement with the problem of radical flux is widely considered a major catalyst for Plato’s development of the theory of Forms, which posited eternal, unchanging objects of knowledge as a direct philosophical response to the Cratylean challenge.