The discussions of both Locke and Vico demonstrate the particular epistemic approach of the Enlightenment in their focus on dissecting the way that thought arises, man’s relationship to nature, and the inclusion of scientific principles, discoveries, and methods into their discourses. In addition, both writers attempt to come to grips with historic and cultural differences that occur between language (within or between cultures) and ideas, the ambiguities and complexities involved in attempting to understand the world, and coming to grips with new ways of knowing informed by science yet still inculcated in religion. Faced with the difficulties of communication across difference, both Locke and Vico sought to find methods of communication and knowledge-building that would reflect the thinking of the time, attempting to offer ways of speaking through or within ambiguities, and thus address rhetorical practices in the process of these inquiries.
Like Bacon before him, Locke grappled with the ambiguities of language that transcended simple categories of definition. As Bacon notes, “even definitions cannot cure this evil [of miscommunication] in dealing with natural and material things; since the definitions themselves consist of words, and those words beget other words” (746). As Derrida would more fully expound a few centuries later, this observation that words define themselves only in relationship to other words with no concrete referent to which they finally point was not lost on Bacon, nor on Locke. For Bacon and Locke, though, there was truth in the material world, but to communicate these truths required words, a human construct filled with ambiguity and potential sites of miscommunication. For Locke, simple ideas (such as “sweet” or “white”) could be demonstrated concretely, and thus posed little problem for communication. Other “mixed modes,” which combined simple concepts to form more complex ideas, became problematic as they moved away from material exerternalities that could be used to signify a concrete concept shared via language.
Though Locke agrees that rhetoric (as it was conceptualized at the time) had a place within society, he argues against its use for the purposes of teaching or transmitting knowledge as he defined it. Because he believed that it was possible to “speak of things as they are,” he eschewed conventional rhetorical practices, or “the artificial and figurative applications of words eloquence hath invented [which] are for nothing else but to insinuate wrong ideas, move the passions, and thereby mislead the judgment” (827). It seems ironic, then, that he would use rhetorical figures to make this very point about the evils of rhetoric at the end of the same paragraph in which he criticized it, as he metaphorically compares eloquence to “the fair sex [which] has too prevailing beauties in it to suffer itself ever to be spoke against” (827). Throughout his entire argument he has used rhetoric to make his points, and yet ends this piece (or at least this excerpt) by criticizing the very methods he employs. Is not “speaking clearly” also a means of persuading, especially for those audiences for whom ethos is predicated upon rationality and scientific methods? This, like many (most? all?) arguments for language that is “a-rhetorical” fall short of their mark for me in that they cannot make those arguments without employing the rhetoric against which they argue. To me, Locke may as well make an argument against language, or in attempting to communicate complex principles through language, because of its ambiguities. It is not possible to effectively argue against a medium while employing it to argue against itself, at least without acknowledging this fact within that argument which, of course, would undermine and largely negate any argument that seeks to do away with something, e.g. in this case, rhetoric for the purposes of teaching or instructing.
Vico, on the other hand, deals more directly in acknowledging the difficulties in communicating across time and place, and even between people speaking face to face.
Rather than seeking to replace the old with the new, epistemologically or methodologically speaking, he seeks to examine both and to take what might be deemed useful from either site. Just as he does not seek to supplant the Ancient with the modern, he likewise does not privilege scientific knowledge over other types of knowing, understanding that all knowledge – including the scientific – are socially constructed. Though he, too, employs the discourse of science in his writing, he does not do so at the expense of privileging the scientific over the social, but rather highlights the importance of both, showing how benefits to society have occurred because of both types of knowing. Though he appreciates the advances of science, he argues against making this the predominant or only way of generating knowledge, nothing that “the greatest drawback of our educational methods is that we pay an excessive amount of attention to the natural sciences and not enough to ethics” (871). This statement is relevant even today and is a critique raised toward practices that seek scientific knowledge as a primary objective, sometimes to the point of ignoring ethical or social harms that may arise as a result.
Because of his grounding in rhetoric and belief that knowing may happen in different ways and result in different outcomes, Vico advocates for the practice of eloquence as a way of understanding and coming to a place of wisdom. To this end, and as part of his larger argument to examine the best practices of both modern and ancient times, he makes a call to his audience to reconsider the role of rhetoric within the university and society, saying, “let us equal the Ancients in the fields of wisdom and eloquence a we excel them in the domain of science,” rather than allowing scientific knowledge superceed all other ways of knowing and thinking. He advocates for students (young men) to learn the ars topica in addition to abstract criticism, as “intellectualistic criticism enables us to achieve truth, while ars topica makes us eloquent” (870). By studying the classic rhetorical methods of finding, constructing, and analyzing arguments, Vico hopes that the educated will be able to more fully understand the probabilities with which they are faced and to gain the wisdom to make ethical choices in the face of this. In addition, he fears that the introduction of abstract, scientific reasoning too early in a student’s career will arrest the imagination, whereas he believes that “at the very outset, their common sense should be strengthened so that they can grow in prudence and eloquence” (870). Though he also believes that the sciences should be taught, as well as intellectual criticism, his focus on also introducing eloquence as an ethical skill that joins knowledge with society – rather than as an act that occurs in a vacuum away from the rest of society – puts him in a similar camp with Isocrates and Quintilian, with a focus on pedagogy and rhetoric as social/civic action.
Comparing the writings of Locke and Vico, I find myself resonating more with the latter. I have studied Vico before (though not this text) as his three-stage model of history (which is actually four-stages, in that there is a “recapitulation” or return from the third stage to the first) is the structure upon which James Joyce based his novel Finnegans Wake, my favorite work of literature. I appreciate his focus on historic and cultural differences, as well as his perspective on the possibilities of rhetoric to support or encourage ethical action. I also appreciate anyone who was able to critique Cartesian methods, as he (Descartes) is often sited as one of the main proponents for the binary split in Western epistemology, which puts him on my “short list” with thinkers like Ramus. It is interesting to me which thinkers/writers were the most well-known, read, and accepted during their times(s) and which ones had the most or least influence over the epistemic stances of their societies. I see these turns throughout history where one path could have been taken but instead another was, or rather where some paths were traveled by more and others traveled by fewer. I try to imagine a “Viconian epistemology” rather than a “Cartesian” one, though of course when I do, dividing them inot these two binaries no longer makes sense in what would, or could be, known as logic.
 By which I assume he means the same thing as topoi?