Monthly Archives: February 2018

Thoughts on theories of truth

Because I’ll be missing class on Thursday, I decided to write a blog post with some of my thoughts about the reading (specifically Glanzberg’s survey of theories about truth in the Stanford Encyclopedia of Philosophy).

At first glance, the Correspondence Theory of truth seemed convincing in its simplicity and its similarity to the truth-conditional theory of meaning. Glanzberg’s slogan for the theory, “a belief is true if and only if it corresponds to a fact” (section 1.1.1), is enticingly intuitive — after all, isn’t truth inherently fact-based? Facts aren’t subjective, nor is truth, seemingly. I interpreted that “the existence of facts is the ‘first truism'” (section 1.1.2) to mean that the existence of facts gives rise to the concept of truth. Although I do think it is important for a theory of truth to describe from what truth arises, I am not convinced of this particular explanation. For one, it doesn’t answer what gives rise to falsity. Perhaps one could say nonexistence does, but that is prematurely introducing a logical negation that operates on bivalent truth values, which presupposes the existence of truth and falsity to begin with.

Here’s a thought experiment (I know “Schroedinger’s cat” is a bit overused, but it serves well to make my point — if you’re tired of hearing about it and just want it to be dead already, just imagine a photon with uncollapsed polarization instead). What is the truth-value of the proposition “Schroedinger’s cat is alive”? I’m not sure how correspondence theorists would handle this. The claim that the statement didn’t correspond to any fact in the real world and was therefore false would imply that the statement’s negation, “Schroedinger’s cat is not alive,” is true, but I would argue it is not, even in a correspondence theorist’s paradigm — in what characteristic(s) of the real world would the fact corresponding to Schroedinger’s cat not being alive consist? Certainly not the cat’s state inside of the box, since that is not only unknown but undecided. Perhaps the corresponding fact could be in the lack of a dead or alive state, but I would argue that that is simply a fact about the nonexistence of a fact. Although that could possibly work, it leaves me unsatisfied. I’m curious to hear what other people think about this thought experiment.

I found Tarskis’ theory of truth (section 2), particularly “Convention T,” difficult to follow. It seems that his theory doesn’t provide a solid, fundamental basis for truth or ground it in the actual world. (I’m sure the recursive nature of his definition of truth contributes to this notion.) One advantage his theory offers, though, is that it determines whether languages are consistent or inconsistent. In inconsistent languages, such as those that contain the Liar Paradox, I gather that truth isn’t a universal quality in that every sentence must be true/false. Perhaps the idea of an inconsistent language could help resolve the questions raised in the thought experiment I proposed in the previous paragraph.

Reading about consistent vs. inconsistent languages led me to the following questions: in an empty language, does truth exist? What about in a language describing an empty world?  To combine what I’m getting at with both those questions, can truth exist without meaning? Can meaning exist without truth? As I see it, truth is not something inherent to the universe. Nothing in the physical world exhibits falsity, I would argue. Falsity seems to arise in a language that is used to formulate propositions, which have truth value. To address the last question, I do think meaning can exist without truth. Consider the Liar Paradox and the opposite proposition, “This sentence is true.” Neither have truth values, but I would argue that they do have distinct meaning.

There’s a lot more to say about all the theories mentioned in Glanzberg’s article, many of which I didn’t even touch on. I will say that I’m most drawn towards the Coherence Theory of Truth, as it seems to hold up under most criticisms, including the “unknown quantum state” thought experiment.

(written by Nicholas Mosier)


Using logical and mathematical tools, formal semantics answers the following questions: Why do sentences mean what they mean? How is reasoning possible? How does language structure our understanding of time, change, knowledge, morality, identity, and possibility? We will assess formal semantics as a theory of linguistic meaning and reasoning by comparing its predictions with linguistic and psychological evidence. We will also examine its philosophical assumptions. This course is well suited for students interested in computer science, linguistics, logic, mathematics, or philosophy. (Some prior familiarity with formal logic is recommended, but not required.)

Course meeting times and places:
Tuesday and Thursday: 9:30AM-10:45AM in Bicentennial Hall, Room 219
Wednesday: 11:15AM-12:05PM in Twilight Hall, Room 302
Office hours:
Wednesday: 2:30PM-3:30PM in Twilight Hall, Room 303A
Thursday: 11:30AM-1:30PM in Twilight Hall, Room 303A