Tag Archives: Correspondence Theory of Truth

Columbo’s Logic, Part 3

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What? You don’t have these yet??

Today, we’re finishing up a look at how Greg Koukl’s “Columbo questions” in his book “Tactics” actually build on what’s called the 3 acts of the mind from classical logic. His first question, “What do you mean by that?”, sought to clarify the words being debated and results in understanding, the first act of the mind. His second question, “How did you come to that conclusion?”, sought reasons for why we should agree to a person’s statement. That is, appropriately enough, reasoning – the third act of the mind. But understanding what someone is saying and why they are saying it both have an end goal: being able to judge whether what they’ve said is actually true, and should be accepted. Getting at the truth is the objective of Greg’s insightful questions, and this requires the second act of the mind – judgment. So let’s jump in and work through that today.

“Judge not” seems to have become the two most popular words to take out of context in all of the Bible,  but judging things (and yes, people) is still necessary. In fact, it’s required for rational thought, for truth can only be discovered through judgment. Judgment is simply to decide on the truth or falsity of a statement. If I decide to drink from the jug of milk in the fridge that I forgot about a month ago, I have mistakenly judged the statement “It’s safe to drink chunky milk” to be true. That is a bad judgment, and one I’ll likely pay for. Knowingly hiring a child molester to babysit your kids would also be a case of very bad judgment. On the other hand, good judgment is valued enough that we even pay certain people to judge other people as their full-time job. We call them… judges. As an engineer, I am given a solemn responsibility to use my “professional judgment” to protect and safeguard the public for whom I’m designing something. But what constitutes good judgment and bad judgment?

Judgment is essentially the relation of two or more concepts to each other to make a statement about them that is either true or false. Judgment is propositional in nature, in that we cannot formulate judgments without forming declarative statements about what we’re judging. Just as in grammar, those statements (or propositions) have a subject about which we have something to say, and a predicate that predicates, or says something about, the subject. I’ve mentioned in parts 1 & 2 that terms and reasoning can’t be true or false, but only clear or unclear for terms, and valid or invalid for reasoning. But here, with propositions, we have a claim being made, and the possibility of it being true or false. We may not know whether the claim is true or false, but every proposition must be one or the other. “This apple is red,” “This chunky milk is OK to drink” “Hitler was a bad man,” “Jesus is God.” Each of those statements relates two concepts (like “apples” and “redness”) in such a way that we must decide if that relation is true or not. If I am holding a Granny Smith apple when I make that first statement, you would be justified in judging it a false proposition, for Granny Smiths are famously bright green rather than red. What warranted that judgment? Simply that my statement did not correspond with reality. While this may seem like common sense, this is technically known as the correspondence theory of truth, namely that truth is what corresponds to reality.  When we are presented with an assertion that we are trying to examine, judgment is needed to decide if the proposition asserted is true or not – if it corresponds with reality. A simple enough statement may be self-evident or immediately verifiable. But many topics, and especially controversial ones, will require hearing supporting statements that must also be judged as true or false.

Let’s look at an example of a modern hot topic. Abortion supporters will often say something to the effect of “my body, my choice” to say that women have a right to an abortion on demand. At that level, it’s only an assertion. But suppose a thoughtful supporter of abortion filled in the premises to that conclusion and said something like, “I have the freedom to do what I want to my own body. Abortion is a procedure done to my own body. Therefore, I am free to choose an abortion.” Although the reasoning is valid (i.e. the conclusion follows from the premises as stated), the second premise is obviously false; there are always 2 bodies involved in the procedure and the successful procedure always results in the death of one of them. If there’s any doubt that the baby is not part of the mother’s body, a simple DNA test can confirm that beyond all doubt. This one’s pretty straightforward since it’s a scientifically verifiable fact that the fetus is not part of the mother’s body. So the supporting premise is false and the original assertion can be dismissed, right? Not so fast. As Peter Kreeft points out in his logic text, “you do not refute a conclusion by showing that it follows from false premises.”[1] The thoughtful opponent could revise their premises to validly support their original conclusion, thus proving their case. So what have we accomplished in judging that premise false? We’ve shown that their case is not as airtight as they had probably assumed. It is inconclusive, and they need to go “back to the drawing board,” so to speak. Encourage them to revise it and get back with you. “Put a stone in their shoe”, as Greg likes to say.[2] Don’t be afraid of what they’ll come back with. If their conclusion really is false, then they simply will not be able to find true premises validly built up to support a false conclusion.

Most of us don’t like to admit we’re wrong about anything. And someone proving us wrong doesn’t make it an easier pill to swallow. So a lot of times, our approach needs to be to help someone see for themselves that their view doesn’t work, because they’re the only one they’ll really listen to. But I’m OK with that. Honest dialogue is like a long journey towards truth together rather than a quick and bloody duel of opinions that goes nowhere. But as ambassadors for Christ [2Cor 5:20], we have this advantage: “Regardless of a man’s system, he has to live in God’s world”[3], and a successful search for real truth, even if it meanders and hits some bumps along the way, will necessarily lead to God, for all truth is God’s truth.

[1] Peter Kreeft, Socratic Logic (South Bend: St. Augustine’s Press, 2010), p. 197.
[2] Gregory Koukl, Tactics: A Game Plan for Discussing Your Christian Convictions (Grand Rapids: Zondervan, 2009), p. 38.
[3] ibid, p144. Greg is quoting Francis Schaeffer here, from Schaeffer’s book, The God Who Is There.

“What is Truth?”

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“What is Truth? Christ and Pilate” – by Nikolai Ge, 1890

“What is Truth?” Pilate asked those words of Jesus almost 2 millennia ago. Johnny Cash had a song with that title back in 1970. Some questions never go away, I suppose. While there are actually several theories of what “truth” is, I want to focus today on the classical version that, I think, is still the best. Let’s dig in!

The classical view of truth is the correspondence theory of truth: a statement is true simply if it corresponds to reality. Aristotle expressed this well when he said that to speak truth is “to say of what is that it is, and of what is not that it is not.” This seems like simple common sense, but since our culture today seems to be struggling with the very notion of truth, let me provide an example.

In engineering, we know that when we idealize a joint, it doesn’t correspond perfectly to reality, and we accept some loss in fidelity in favor of simplification for analysis… to a point. But sometimes we have to say, “This has gone beyond simplification and is now misrepresenting the object being analyzed.” Our model doesn’t correspond to the real object anymore.

For instance, we tend to model truss joints as being “pinned” – i.e. not rigid. And for most trusses like the open web steel roof joists you might see in a retail store, that’s a relatively accurate model.

Now compare that “simple” pinned truss joint to a giant truss joint like the one pictured here. That’s a pretty beefy connection and probably more accurate to assume a high degree of stiffness in that joint. Somewhere in between those 2 extremes, our model passes a point of unacceptable noncorrespondance to real joint behavior. What about these in-between situations? Just because that point is in a gray area doesn’t mean we deny the idea of truth being what corresponds to reality. Sometimes, in critical applications, it’s warranted to invest the extra work in modeling the joint as a rotational spring to capture that behavior in between a rotating pin or a fully rigid joint. Likewise, in diaphragm design, we are allowed to assume flexible or rigid diaphragms for the obvious extremes like thin metal or wood decks versus thick concrete slabs. For those unclear areas in between, we use the more accurate method of a “semi-rigid” diaphragm using a finite element analysis to analyze our floors or roofs. Why? Because our profession recognizes that truth still exists, even in gray areas. It’s just more difficult to ascertain, and requires more thorough investigation to find it. So in real life, the existence of gray areas and difficult situations doesn’t preclude the existence of a “right”, or true, answer; rather, what we are recognizing when we classify something as a gray area is our uncertainty of the truth we are seeking in those situations.  But we stillrecognize that the truth is there, somewhere, or else we wouldn’t seek more accurate answers. And this recognition of a reality holding the right answer, outside of our own interpretations of reality, points to the premise that truth is objective and not subjective. In other words, the truth about an object is based on the object itself, not on our subjective perceptions of it.  If I’m colorblind, I might perceive an object’s color very differently from another person, but the object is absorbing and reflecting photons of light in a manner independent of either observer. Therefore, the true color of the object is based on the properties of the object itself, and I describe the object truthfully when I call it by the color it has rather than the color I think I see.

Gray areas in moral and ethical questions are often used to undermine the idea that there are objective moral truths as well as physical truths like my examples above. Yet this is a similar situation to those examples: just because we can recognize the right answer in the easy,  obvious cases doesn’t mean there isn’t a right answer for those less-obvious cases. It just means we might have to dig a little deeper, and possibly remain unsatisfied with potential answers until we find the right one.  But there’s a shortcut, of sorts. The one true God who created the physical universe with its objective physical truths also established the moral truths we seek.  In God, we have that independent “third-party” that can referee between competing truth claims from different people, cultures, times, or places. And who better than the very source of moral truth, for whom it is impossible to lie? [He 6:18, Ti 1:2] Until next time, never waver in the relentless pursuit of truth!