Language and Psychologism

Yesterday I made a strange claim, namely that seeking logic in language and speech acts is a kind of psychologism. The idea is that the specific languages we study and the content of the speech acts are arbitrary. It doesn’t matter if we speak of English or French (though it may matter, of course, when considering non-European languages), and it doesn’t matter what the speech acts are about. Whether we seek to understand negation with the English ‘not’ or the French ‘non’ should amount to the same logical analysis. And whether we are talking about things that are not frogs or things that are not elephants shouldn’t change the logical analysis of negation.

But it’s precisely this arbitrariness of language and abstraction of content that suggests language itself isn’t where the logic is. Let’s consider a more concrete theory, by Hlobil and Brandom, an inferentialist theory that explores “reasons relations” found in the speech acts of assertion and denial. The validity of an argument can be analyzed by saying that one would be wrong to assert all the premises and deny all the conclusions.

Assertion and denial, however, do not require words or language. I can shake my head to say ‘yeah’ or ‘nay’. Indeed, I don’t even need to express assertion and denial in any kind of way when I’m alone. I do something when I accept premises and reject conclusions, but that doesn’t necessitate a speech act of assertion and denial.

But that’s where I see psychologism creeping in. I suggest that acceptance and rejection are more fundamental psychological attitudes than assertion and denial, and in fact, the psychological act that grounds the speech acts. I’m a bit confused with this chain of thought, so I’m not offering this here as the argument behind a belief I have. I’m genuinely exploring a difficulty I feel at the intersection of language and logic. Is this a real difficulty? Not sure.

Language, Thought, and the Grounding of Logic

Language has come to take a central place in Twentieth-century analytical philosophy. It’s as though language became the lens through which we inspect thought and discover truth. I’m not saying that thought is where truth resides, but rather that the expression of thought is what reveals truth. We can’t put people in scanners that will reveal their thoughts so we can assess if they are true or false. Even if we could, it’s not clear that this would become a fundamental methodology. Why? Because figuring out philosophical truth isn’t a descriptive or empirical project, as would be, for instance, the observation of stars in the universe. Yet, we engage in philosophical enquiry with thought, and we develop it in language.

Since so much of what we know and learn depends on language, it is no surprise that language use is very important. For instance, it matters whether the commandment that "you shall not kill" is about killings or murders. What we mean by the commandment is very important, and what we mean depends on how we think about it and express it in language. Thus, language has taken centre stage in philosophical investigation.

Now, what about logic? The same reasoning applies: logical reasoning is expressed in language, and language use is crucial to understanding logical reasoning. Yet, there’s a difference between studying language use as a proxy for logical reasoning and exclusively studying language to ground logic.

Here’s the thought I want to get at. While language is important to logical reasoning and speech acts reveal a lot about logic, the specific words we use are rather inconsequential, as is the language (e.g., English, French) that we know and use. Indeed, it’s conceivable that what is central in a speech act that reveals reasoning is the goings-on at the level of thought behind the linguistic expression. But if logic is grounded in language, and language only reveals the thought process, doesn’t it follow that logic is grounded in thought? And if so, isn’t the study of language really the study of human psychology? And if so, doesn’t this ultimately ground logic in psychologism?

Social Logic

Social epistemology is a field of philosophy that studies knowledge not as it is held by individuals, but as it is shared in communities. Once we consider a social perspective, questions about knowledge arise that weren’t salient for individuals. How do we come to know things from others? How can we trust others to have the right kind of justification for a belief to count as knowledge? Is group knowledge always reducible to individual knowledge? Or is it possible for new knowledge to emerge once individuals get together and pool their individual knowledge?

Social epistemology forces us to look at praxis, where theory and practice meet. In praxis, a question that quickly becomes important is when we can rely on testimony. In the community, we often have to rely on the knowledge of others. I know that right after I was born, I looked up to my mother with big brown curious eyes. How do I know that? Because my mother told me, and I fully trust her testimony. But I don’t trust the testimony of the Hill couple, a famous case of alien abduction that I go over in detail in *Logic in the Wild*. I trust the sincerity in their reports of the events, but that they believe it was an alien abduction that best explains the weird course of events they experienced doesn’t make me believe in their version of the story, let alone grant me knowledge of it.

Now, is there a corresponding way to think about logic at the social level? What might social logic look like? What happens to coherence when we pool individuals’ perspectives? One thing obvious is that all individuals could have coherent stories, but theories that clash when they are put together. How are we to resolve incoherence in such cases? And what about the logical aspect of testimony? A testimony has to be told in a coherent fashion to be communicable, but what logical standards are appropriate in receiving the testimony? Circling back to the Hill couple, I think their testimony is coherent, but of course coherence doesn’t lead to truth.

What if, however, they weren’t only retelling a weird story that happened to them overnight, but a story that involves paradoxes? Or perhaps they are expressing something in a worldview that appeals to holistic conceptualisation whose coherence cannot be recognised from an orthodox logical point of view. Can logic be influenced in such social contexts?

From Coherence to Computers: Logic's Unseen Influence on Technology

If logic serves as the guardian of coherence and sidesteps content or truth, one might wonder about its significance in society. How can a discipline that seemingly detaches itself from reality exert any influence on our daily lives? In "Logic in the Wild," I tackle this question from a practical standpoint. I demonstrate how prioritizing coherence over truth enables us to navigate through complex phenomena when truth is elusive, reconcile new information that contradicts our pre-existing beliefs, or engage constructively with others holding divergent viewpoints without descending into disputes over content or truth.

Moreover, there's an intriguing narrative highlighted by Martin Davis in "The Universal Computer," which credits logic with the inception of the computer. Far from being mere collections of software, computers are, at their core, embodiments of logic. This journey begins, not with the ancients or medieval logicians, but in the 17th century with a young boy. He harbored what he described as one of the "greatest ideas of all times"—the vision of a perfect language capable of articulating all truths. This boy was none other than Gottfried Wilhelm Leibniz, who, as an adult, often boasted about this groundbreaking concept in various letters. Leibniz's vision included not just the perfect language but also the notion of a machine that could operate using this language, enumerating all truths and, by extension, becoming the ultimate repository of knowledge and truth.

Leibniz indeed engineered some simple yet ingenious mechanical devices capable of performing basic arithmetic operations. However, beyond these inventions, his contributions to logic largely consisted of him bragging about his groundbreaking ideas in various letters. The narrative progresses to the 19th century with the mathematician Gottlob Frege, who initiated a renaissance in crafting a perfect logical language. Building on centuries of mathematical advancements, including those by Leibniz, Frege laid the groundwork for what we now recognize as Classical Logic.

It was the English logician Alan Turing who bridged the theoretical with the tangible by devising the concept of the Turing machine, the precursor to modern computers. It took approximately five decades to evolve the technology necessary to actualize this theory, but the culmination of these efforts was the realization of Leibniz’s dream: a perfect machine operating with a perfect language.

So, if the abstract study of logical patterns and the coherence of beliefs and theories seem distant from practical utility, consider the computer as a resounding rebuttal. Through logic, we not only enhance our understanding and interactions but also pave the way for technological marvels that define our contemporary existence.