Truth is unassailable. It is not possible to attack the truth (capital T), without making use of truth claims. Consequently, attacks on truth generally result in self-defeating contradictions. Consider a few examples:
- There is no such thing as truth. This statement itself is a truth claim.
- Truth is not absolute. To which we might respond, “Are you absolutely sure?”
- All truth is relative. All is an absolute term and this is an absolute truth claim.
- That’s true for you but not for me. Is this truth claim true for you but not for me?
Recently at The Daily Apologist, we promoted this concept of truth and its application to important metaphysical and ethical claims by posting the following quote by Norman Geisler on our Facebook page:
Contrary to what is being taught in many public schools, truth is not relative but absolute. If something is true, it’s true for all people, at all times, in all places.
Our post received the following interesting response:
"Today is Friday". This statement is TRUE. However this statement will be FALSE tomorrow. A simple example of relative truth.
So, what’s going on here? Is this an instance of relative truth? The answer is no. Let me explain. Consider the following sentence:
I am writing this blog today.
This sentence contains words known as indexicals, expressions “whose content varies from one context of use to another.”
The meaning of this sentence is relative to a person, a world, and a time. Notice, I is an indexical term that refers to me (Nathan) and not to you or to anyone else. This, a demonstrative pronoun, refers specifically to the blog titled, Are You Absolutely Sure Truth is Absolute? Today refers to one particular date, September 5, 2018.
The truth value of this sentence, however, is not relative. It is absolute. Look at it this way -- if we replace the indexicals in the sentence with their referents, we have an objective and absolute truth claim:
Nathan is writing Are You Absolutely Sure Truth is Absolute? on September 5, 2018.
This claim affirms a certain objective state of affairs. As such, it is subject to evaluation in the same way that any other truth-claim (The sky is blue. Grass is green.) is – by a comparison to the actual state of affairs. In this case, this claim is true. And, it is absolutely true. It’s not "true for me but not true for you." It is true for all people, at all times, in all places. So, though its meaning or content is relative to a context, its claim is actually objective and its truth value is absolute.
The same holds for the example given by our reader. “Today is Friday” is actually an objective claim whose meaning is context-dependent, but whose truth value is absolute. When we translate the indexical in this sentence (today), the state of affairs affirmed is:
August 24, 2018, is Friday.
Now, when we compare this claim with objective reality (we look at a calendar), we find that it is absolutely true. Similarly, our reader notes that it would not be true on the next day. Let’s see what that affirms:
August 25, 2018, is Friday.
Again, our reader is absolutely right. This statement is false. August 25 was a Saturday. Interestingly, our reader made absolute claims about the truth value of these two sentences. It would seem, in fact, that he agrees with us that truth is, indeed, absolute.
To summarize, indexical statements are context-dependent for meaning but absolute in terms of truth-value.
[We would like to thank our reader for sharing their interesting response as it prompted this helpful study.]
 Geisler, Norman L.; Turek, Frank. I Don't Have Enough Faith to Be an Atheist (Chapter 1). Good News Publishers. Kindle Edition.
 Ibid., location 607-608.