1.4: Distinction of Proof from Verification; Our Biases and the Forer Effect

Proof vs. Verification⁸

When you make observations, you gather evidence toward some new knowledge. Observations are just points of information that you can use as a building block with other bits to eventually arrive at new knowledge and understandings. But how exactly does information relate to our knowledge? It can do so in two ways: by proving something new or by verifying (or confirming) what we already know.

Verifying is the easier concept to understand and is also usually what we mean we use the word proof. For example, we say,

Her breath smells like chocolate, so it proves what we already know: she ate the chocolate!

We’re not proving anything. We’re just verifying what we already knew and adding evidence to support the claim that we’ve already accepted. How did we accept this claim in the first place? We proved it.

Proof, therefore, works a little differently. When something is proven, we have learned something new. There is nothing to verify since we don’t know what it is we’re looking for. Proofs use observations and knowledge to get us to a new claim with the proper support that is required in order for us to accept the truth of the new claim we have uncovered. For example,

I set out a box of freshly imported Belgian chocolates on the table before heading to the restroom. When I returned, the box had been emptied. I wanted to find where it went. I suspected that Mary had eaten my chocolates, but I needed to prove it before I cast blame on her. A trail of chocolate was left on the floor so I followed it into the next room. In that room, sitting in a chair, I caught Mary brown-handed, eating chocolates, and I even saw the last one as it entered her mouth. I said, “A-ha! You ate my chocolates! The evidence proves it!” to which she did her best Shaggy impression (look it up if you don’t get this), and said, “Wasn’t me!” I leaned in to smell the distinctive smell of my precious brown gold that was recently pilfered. Her breath smelled like chocolate, so it verified what I already knew: she ate the chocolate.

The takeaway point is just this: with every bit of new information you receive, see how it fits into your beliefs and analysis and be sure you use it properly to either come to a new conclusion or support one you already have.

Facts, Values, and Biases

One thing to keep in mind is that everything we do is colored by our own views, beliefs, and experiences. We think that we know “facts” and that these are indisputable. It doesn’t matter how we feel about them: facts are true, and objective evidence tells us this. While this is how we will behave on a daily basis, many philosophers a lot smarter than myself (notably W.V.O. Quine) have shown that this simply isn’t true. Presumably, there is a distinction between what we think of as “facts” and “values”. This is actually called the fact/value distinction, and it was generally assumed that there was a clear line between the two: something was either a fact or value. For example,

FACT: The sky is blue.

FACT: US Independence is celebrated on July 4.

FACT: Tuesday is after Monday.

VALUE: Coconut is disgusting.

VALUE: Blue is pleasing on the eyes.

VALUE: Kindness is a good trait.

In truth, facts and values are not distinct: in each there is at least a hint of the other. There will always be a value in a fact by the sheer “fact” that we call them “facts.” Why is it that we choose to say it’s a fact that “Tuesday is after Monday”? There must be something valuable about that statement that makes us want to identify it as a fact. “The sky is blue” is only a “fact” because we generally observe it to be a blue, an observation that is necessarily subjective since we all see colors differently. Finding the facts in values is much harder to do, and in all honesty, I have never understood the reasoning completely myself. The lessons from understanding that values are present in facts is what is important: recognize that no matter how hard the truth or fact is that you are claiming, your biases have influenced you to use them in ways you may never know.

The Forer Effect⁹

The Barnum effect, also called the Forer effect, is a common psychological phenomenon whereby individuals give high accuracy ratings to descriptions of their personality that supposedly are tailored specifically to them, that are in fact vague and general enough to apply to a wide range of people. This effect can provide a partial explanation for the widespread acceptance of some paranormal beliefs and practices, such as astrology, fortune telling, aura reading, and some types of personality tests.

These characterizations are often used by practitioners as a con-technique to convince victims that they are endowed with a paranormal gift. Because the assessment statements are so vague, people interpret their own meaning, thus the statement becomes "personal" to them. Also, individuals are more likely to accept negative assessments of themselves if they perceive the person presenting the assessment as a high-status professional.

The term "Barnum effect" was coined in 1956 by psychologist Paul Meehl in his essay Wanted – A Good Cookbook.