By Contributing Editor Andrew Hines
The theme of the relationship between language and rationality has resurfaced as of late. This is not in the least due to concerns about “post-truth” that have emerged from a political landscape in which rhetoric takes on a life of its own, divorced from the necessity of facts or rational argumentation. Some commentators have suggested the blame lies with twentieth century French thinkers such as Lyotard or Derrida. I am sorry to have to tell the reader that the re-evaluation of language’s relationship to rationality is much older. While post-war French philosophy has undoubtedly had a dramatic influence on the trajectory of Western thought, its relevance to the relationship between rationality and language is part of a longer story that goes beyond radical developments in cafés on the Parisian left bank.
One particularly poignant chapter of this story is the transformation of the West’s view of the relationship between rationality and metaphor in 19th century German thought. Metaphor, the device of figurative language which Aristotle famously described as “the application of a word that belongs to another thing”(1457b), was given a distinct relationship to reason in the Enlightenment by Hobbes and Locke. They recognized metaphor’s power to persuade, but for them such persuasion operated in all of the wrong ways. While they believed that metaphor had entertainment value as a poetic device, they also believed it should be avoided in rational argumentation because it was illusory and led one’s thinking away from the truth (26, 36; 372). Other Enlightenment thinkers, such as Vico and Rousseau, were more charitable but metaphoric expression and rational thought were still viewed as distinct categories.
What is startling about 19th century German thought is the way in which this distinction was transformed. We could cite many episodes in this story such as Gustav Gerber’s distinct understanding of Lautbild (a phonetic or articulated image) or Heymann Steinthal’s notion of linguistic relativism. But one episode in particular encapsulates the transition from the view of the human being as the rational animal to the human being as the metaphorical animal: the influence of Max Müller on Friedrich Nietzsche.
This transition was set against a backdrop in which various 19th century German thinkers were grappling with the implications of Schlegel’s historical comparative method and Christian Gottlob Heyne’s and Friedrich August Wolf’s approach to language. In this approach art, religion, customs, and usage were considered equally important to the mechanics of grammar. Thus, as Benedetta Zavatta has put it, some thinkers in this period had an ‘anthropological interest’ in language because they viewed language “in relation to the man who speaks it”(285). This “anthropological interest” interest in language reframed the question about the relationship between language and rationality. Why? Because it allowed space to question the ability to judge between rationality and the aspects of language, deemed, from the perspective of thinkers like Hobbes and Locke, as productions of poetic fancy, such as metaphor.
Müller is significant because while he is widely known for his assertion that mythology was a “disease of language,” it is less recognized that metaphor is in fact central in this notion (129 – 130). This reminds us that, for Müller, metaphors play a central role in the formation of abstract concepts. Yet, as we shall see, it also shows us that Müller is still firmly committed to a distinction between metaphor and reason where one can judge between the two.
In Müller’s Lectures on the Science of Language, he called language “the one great barrier between the brute and man… Language is our Rubicon, and no brute will dare to pass it” (392). This quotation reflected Müller’s anthropological interest in language and how he held on to language as a demarcation of what it meant to be a human being. When a human being used language, from Müller’s perspective, he or she used language as a rational being that is distinct from the irrationality of animals. This commitment to the human being as the rational animal also appeared in Müller’s famous notion of mythology as a ‘disease of language’.
The phrase “disease of language” referred to Müller’s suggestion that key features in a myth, such as the name of a god, were metaphorical descriptions of natural phenomena. However, these metaphors were imbued with anthropomorphism and over time become more substantial. One example of this can be seen in Müller’s long essay “Comparative Mythology.” There he wrote about the gendered nouns in Greek or Sanskrit. He said that because of these gendered nouns it was ‘simply impossible to speak of morning or evening, of spring and winter, without giving to these conceptions something of an individual, active, sexual and at last personal character’ (72–73).  Gendered nouns inevitably anthropomorphized their subject because they projected a human characteristic – gender – onto natural phenomena like morning or spring.
Müller famously generalized this idea to show the way that language works in the creation of mythology. He wrote, “Mythology…is in truth a disease of language. A myth means a word, but a word which, from being a name or an attribute, has been allowed to assume a more substantial existence. Most Greek, Roman, Indian and other heathen gods are nothing but poetical names, which were gradually allowed to assume a divine personality never contemplated by their original inventors. Eos was a name of the dawn before she became a goddess, the wife of Tithonos, or the dying day” (12).
As Andreas Musolff has pointed out, for Müller metaphor created a “fundamental misunderstanding” in thought (129 – 130). The reason that Müller called it a misunderstanding at all, comes back to the view we have seen where Müller asserted that language was a unique human phenomenon and indicative of an underlying rational mind.  Therefore, it followed that, for Müller, “the disease of language” was apparent because there was a clear line between the natural phenomenon, the metaphor and the figurative expression used to describe it.
Nietzsche appropriated this idea in a subversive way. Nietzsche is perhaps the most famous for his critique of propositional truth via metaphor when in ‘On Truth and Lying in a Nonmoral Sense’ (1873), he wrote, “What, then, is truth? A mobile army of metaphors…”(146). Müller became central to this famous critique when Nietzsche appropriated him to explain metaphors role in the creation of truth claims:

[Truth is] a sum of human relations which have been subjected to poetic and rhetorical intensification, translation…and which after they have been in use for a long time, strike a people as firmly established, canonical, and binding; truths are illusions of which we have forgotten that they are illusions, metaphors which have become worn by frequent use and have lost all sensuous vigour, coins which, having lost their stamp, are now regarded as metal and no longer as coins (146).

When Nietzsche was trained as a philologist in Leipzig by F.W. Ritschl and Georg Curtius he encountered Müller’s work and also frequently borrowed it from the university library in Basel (273 – 274). However, while Nietzsche clearly drew on Müller’s ideas, he took them a step further when he wrote, “the intellect shows its greatest strengths in dissimulation, since this is the means to preserve those weaker, less robust individuals who, by nature, are denied horns or the sharp fangs of a beast of prey with which to wage the struggle for existence” (142).   This ‘disease of language’ as Müller would call it, was the greatest strength of the intellect according to Nietzsche. For Nietzsche, dissimulation, calling a natural phenomenon by a metaphorical description that relates to a divine personality, was not some aberration of rationality, like it was for Müller, rather, it was the greatest strength of our intellect. He uncompromisingly asserted that metaphor was the rule and law of cognition when he wrote that it was “that fundamental human drive which cannot be left out of consideration for even a second without also leaving out human beings themselves” (150–151).
This does not simply critique truth. Rather, with Nietzsche’s subversive reading of Müller, he collapsed the gap between metaphor and reason and transformed the Aristotelian rational animal, which Müller held up as the clear distinction between ourselves and animals, into something we might call, a “metaphorical animal,” as the French philosopher Sarah Kofman so poetically put in her book Nietzsche and Metaphor (1983) (25).
The intellectual-historical question this poses for us regards the trajectory of the relationship between our western conceptions of rationality and of metaphoricity. A re-evaluation of the relationship between these concepts in this period could shed light on the still murky relationship between them across a number of fields, including post-war French philosophy and cognitive metaphor theory. Politically, the question it poses to us is much more pragmatic: whether we can detect reason’s error, whether we can distinguish between dissimulation, between truth and lying is perhaps irrelevant. For as Nietzsche also wrote, while truths are simply metaphors that “strike a people as firmly established, canonical, and binding,” the fact that they strike us as canonical and binding, help us to create “peace treaties.” However relative these peace treaties may be, they help society to prevent a Hobbesian “war of all against all” and enable communication (143).  Perhaps, what matters most about metaphor in the age of post-truth is whether we want to see the world shaped by these new attempts at “peace treaties.” If not, what are the alternatives besides a nostalgic yearning for good old rationality and rhetoric that plays by the rules?
Dr. Andrew Hines studied at both the University of Oregon and the University of Tübingen, obtaining a BA in Philosophy. He also holds a MA in Philosophy from University College Dublin and a PhD in Comparative Literature from Queen Mary, University of London. His thesis was on the concept of metaphor in European philosophy after Nietzsche. A specialist in the history of metaphor theory and post-Kantian European philosophy, he is more broadly interested in the political power of language, the history of ideas, and the relation between philosophy and cognitive science. He has written for The Conversation, The Huffington Post, and Newsweek.