8.7: Truth vs. Validity

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Jim Marteney
Los Angeles Valley College via ASCCC Open Educational Resources Initiative (OERI)

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So, now let’s go back to the Jim and Suzy story. Both of their conclusions are valid, that is, internally consistent with the evidence they used to come up with their conclusions. We would use the process of argumentation to try and determine which conclusion was the most valid. But which position is True? The best answer, from a critical thinker’s perspective would be, “we don’t know.”  Why, because, the argumentative process is not capable of determining the ultimate Truth. Critical thinking is focused on validity.

Measuring Validity

Validity is not an all or nothing score. In Chapter Three we looked at Dr. Littleton’s Model of the Bead of Truth, where he measured validity along a wire between 0 and 1. Now it is time to look more closely at that measurement scale and define some of the points between the two extremes.

The Continuum of Argumentative Certainty is a measurement of how sure you are on a claim that is being made from totally uncertain to ninety-nine percent convinced. As we have seen, a good critical thinker is never 100% convinced of anything, that way they stay open minded.

The more you move from the left to right, the more likely you are to accept the claim as being correct. The critical thinker starts on the left side. As he or she hears more and more convincing information, they are likely to be moved up towards the right-hand side of the scale. Moving from a low percent certainty to a higher percent certainty, we become more likely to accept the claim being made. We may treat these different levels on this scale in a somewhat vague manner, but science attempts to be much more precise.