In a posthumously published essay, “The unknown Xenophanes: an attempt to establish his greatness” (in The World of Parmenides, London: Routledge, 1998), Karl Popper presents Xenophanes as no less than the “founder of the Greek Enlightenment” (33). With some justification, Popper attributes to Xenophanes the modest epistemology of the Popperian scientist, who never claims more than conjectural knowledge, and whose theories can be proved false but never true. Nor can we deny that this long-lived son of Colophon says things about sacred beings we will not hear again until the time of Voltaire—although the conjunction of Xenophanes’ epistemological modesty and his transcendental theology makes him an Enlightenment figure in the mold not of Voltaire but of Kant.

Xenophanes is best remembered today for two fragments: “Ethiopians say that their gods have snub noses and black skin, Thracians [today’s Slavs] that theirs have blue eyes and blonde hair” (Fragment 16; the text and the sometimes-modified translations are taken from Xenophanes of Colophon by J. H. Lesher, U of Toronto P, 1992); and “if horses or oxen or lions had hands . . . horses would draw the figures of the gods as similar to horses, and oxen as similar to oxen, and they would make the bodies of the kind that each of them has” (15).

Popper is particularly impressed with the evidence in Xenophanes of a near-Kantian critical distinction between ultimate truths and our certitude about them. Fragment 34, of which Popper says that “to me there is nothing in the whole literature of philosophy that is so critical, so self-critical, so correct, and so true” (46), is of particular significance:

And of course the certain truth no one has known
Nor will know, about the gods and what I say about (all) things,
For even if, at best, one happened to speak [the truth of] what has occurred,
Still he himself would not know it; but opinion/seeming is allotted to all.

This is a strikingly modern epistemological intuition: one might perchance speak the truth, but one cannot know its truth. Parmenides’ solution, as we have seen, was to limit the domain of true statements to the what-is, or in modern terms, to conceptual logic. As noted in Chronicle 372, like all pre-Socratic epistemologies, that of Parmenides lacks a clear distinction between meaning and reference. We should not assume that Xenophanes, Parmenides’ predecessor (some say, his teacher) has made this distinction; denying that we can know what Kant would call “things in themselves” does not lead Xenophanes to define a purely conceptual domain in which statements may be “analytically” true independently of “what has occurred” in the real world. The positive element in this conflation is that, in contrast with metaphysical philosophy to come, Xenophanes’s epistemological concern is centered on the sacred, which he understands to be the basis for all worldly knowledge. Language can model the world only because it first pointed to the gods.

Whether or not Xenophanes had a direct influence on Parmenides, the filiation between the two is plausible; rather than revealing, like Heraclitus, “invisible” processes behind apparently stable realities, Xenophanes accepts the impossibility for a human to have certain knowledge of a world ruled by a transcendental power. For Xenophanes, the limits of human knowledge are not simply the limitations of perception; they reflect the intuition that human language is separated from its originary source, that worldly experience cannot fully justify it. This is the negative moment of the metaphysical understanding of language as providing models of reality. Xenophanes’ rejection of the black or blond god corresponds in the visible realm to the Hebrew elimination of God’s vocative name; if the transcendental Being cannot be figured, it cannot be called upon either. But if this ostensive guarantee is missing, then language can seek its guarantee of validity only in itself, in the what-is of Parmenides’ Way of Truth. The very notion of a proposition as embodying “truth” as opposed to “opinion” can only be raised once its ostensive guarantee is no longer available.

Among the classical scholars of the pre-Socratics, Gregory Vlastos was perhaps the most sharply conscious of their religious (and not merely philosophical) significance. In “Theology and Philosophy in Early Greek Thought” (in Studies in Presocratic Philosophy I, London: Routledge, 1970, originally in Philosophical Quarterly 2, 1952), critiquing Werner Jaeger’s Theology of the Early Greek Philosophers, which understates the distinction between the theologoi such as Hesiod and the pre-Socratic philosophers, Vlastos raises the pertinent issue of the respective relationship of both groups to “cult” or ritual practices: the Pythagoreans engaged in such practices, but none can be reasonably associated with the speculations of Heraclitus or Anaximander, or even Xenophanes. Vlastos pertinently distinguishes the pre-Socratics’ religious doctrines, for which the divinity embodies as laws the regularities that govern the universe and that the philosopher sees as his task to discover, from theogonies based on ritual whose capricious gods reveal themselves precisely by their ability to violate natural regularities, which are attributed to necessity (ananke) but not to the gods to whom one sacrifices. The key passage is the following:

[T]he unique achievement of the Presocratics as religious thinkers . . . lies in the fact that they . . . dared transpose the name and function of divinity into a realm conceived as a rigorously natural order, and therefore, completely purged of miracle and magic. . . . The prophets of Israel and Judah fought a valiant rear-guard action against wizards, necromancers, and soothsayers. But they lacked the conceptual equipment to see that magic was not only a religious impropriety but a sheer impossibility; and they never cleared their minds of the notion of miracle which is the intellectual foundation of magic. . . . To present the deity as wholly immanent in the order of nature and therefore absolutely law-abiding was the peculiar and distinctive religious contribution of the Presocratics, and it should be put in the forefront of any account of their religious thought. They took a word which in common speech was the hallmark of the irrational, unnatural, and unaccountable and made it the name of a power which manifests itself in the operation, not the disturbance, of intelligible law. The transposition opened new religious possibilities. Had these been realized, Greek religion would have been freed of those evils which Lucretius in retrospect so justly imputes to it. (199-20)

This thinking expresses a profound anthropological intuition, but developed along metaphysical lines. What is missing is the link between ethical and cosmic totality. As we have seen, the application a la Anaximander of legal terminology to divine transcendence is above all a reaction to the ethical disequilibrium of the hierarchical society that had grown up under the protection of the old ritual culture. The notion of a divine law governing the cosmos as opposed to a capricious divinity who can be influenced by ritual or magic reflects the same development we see in the Mosaic revelation of the “nameless” god. If there is a difference in the social basis of these two parallel revelations, it lies in the fact that the Greek city-states experienced hierarchical inequality as an internal problem, whereas the Hebrews were faced in addition with problems of national submission, not to say, survival. To experience one’s “own” god as the One God is a deeper source of revelation when one loses a battle than when one wins. Thus the persistence of “miracles” in the thinking of the Hebrew prophets reflects the continuity of genuine religious activity within the framework of the Mosaic revelation, a phenomenon that Vlastos is not concerned to distinguish from the archaic ritual cults he describes in Greece. The pre-Socratic deity who is absolutely and therefore necessarily “law-abiding” is not a god but a metaphysical construction. Hebrew religion remembers what the pre-Socratics were in the process of forgetting: that a wholly immanent divinity, or in more neutral terms, a wholly immanent anthropology, is incapable of providing the ethical basis for a functioning social order. The genius of philosophical speculation is that it occurs in the margin of the central religious institutions of its society; in recent times, the only serious attempts to replace religion by philosophy have ended in disaster.

Xenophanes’s long, much-traveled life exemplified the Greeks’ experience of cultural plurality that underwrote their liberation from the “compactness” of ritual culture. Xenophanes’ disagreement with mortals who “suppose that gods are born, wear clothes, have a voice and a body” (14) makes clear that he considers the attribution of specific traits to the divinity as not merely empirically groundless but a category error. Xenophanes’s wholly transcendent divinity, lacking in differential qualities, is perforce unique. Thus he speaks of one god who is “greatest among gods and men, not at all like mortals in body or in thought (23).” God sees, thinks, and hears “the whole” (24); he abides always in the same place (26); he “shakes” (kradainei) all things by the [mere] thought of his heart/lungs/mind (freni) (25). Xenophanes does not always insist on the uniqueness of his god. But when he says, “not from the beginning did gods intimate all things to mortals, but as they search in time they discover better” (18), the plural is inconsequential; what is important is the nearly explicit opposition between transcendental truth and human knowledge that can only improve its approximations to it.

Xenophanes’ reference to the gods of the Ethiopians and the Thracians is not satirical; it might almost be called ethnographic. Taken as a reductio ad absurdum, it leads to a purely transcendental conception of the sacred. But it can also be read as a statement of the necessary limits of the human religious imagination, in the sense that even when we recognize that the divinity cannot “look like us,” we have no better way of conceiving him (or her). Taking this point to its ultimate conclusion, we would interpret the constraint of the human imagination not as a sign of limitation but as a guarantee of truth; this would lead us to the Christian notion of a human “person” of God. That Christianity obliges us to encounter once more, and with a vengeance, the plain fact that a historical incarnation of God cannot “look like everyone” reminds us on a higher level of the historical particularity of both human origin and Hebrew monotheism.

Xenophanes’ theological conceptions may be said to parallel those of monotheism, but in their abstraction they cannot duplicate monotheism’s world-historical impact. Vlastos justly notes the lack of “conceptual equipment” that prevented the “prophets of Israel and Judah” from eliminating all vestiges of magic and miracles from their religious vision. But nothing in the pre-Socratics nor in Greek philosophy as a whole embodies the new conception of religion with the profundity and force of the biblical Ehyeh asher ehyeh. The ultra-Parmenidean truth of the divine self-contained being who names himself with a proposition could be revealed only through the “miracle” of a conversation between God and man.