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7. What Is Science?: Proof

Okay, we’ve made an observation, hypothesized as to the cause, and performed some experiments to test the hypothesis. At what point do we have a proof?

When you say something and someone says to you “Prove it,” what kind of proof is he or she looking for? Chances are that subconsciously he or she is expecting a scientific proof. Herein lies the problem. As you’ve probably guessed, it isn’t as simple as we would like. It turns out there are at least two kinds of proof that matter in day to day life—scientific and legal-historical (LH). (There are also mathematical and statistical proofs, but I’m lumping them in with scientific proof, as they relate less to daily life.)

Scientific proof can be loosely defined as follows: Every time A and B occur, C results. If C doesn’t happen, then something is different about A and B, but as long as only A and B occur, C will result. In other words, if you let go of your pen, it falls. In fact, every time you let go of your pen, it falls. As long as you are inside a reasonably effective gravitational field, that stupid pen falls towards the center of the field. If all of a sudden, all else being equal, it didn’t fall, you would know instantly that all else isn’t equal—one of your starting conditions has changed. Scientific proof is based on the repeatability of events. If you have the specified conditions, you can expect a specific result. If you get a different result, then the starting conditions had to have changed. A rather corny joke illustrates this principle:

A chemist, mathematician, and engineer all lived on the same street. One night, the mathematician’s house caught fire. In an effort to minimize the damage, he calculated exactly the correct amount of water to just put out the fire, and gave the result to the firefighters. Of course, it took so long to get the answer that the house burned to the ground.

A few nights later, the engineer’s house burned. Not wanting to repeat his neighbor’s mistake, and understanding the general principle that ‘close enough is good enough,’ he instructs the firefighters to put it out as quickly as possible. They dump water on the fire and put it out immediately. However, there was so much water damage it was still a complete loss.

Well, you know how these stories go. The very next week, fire erupted at the chemist’s house. {The real joke here is that it was the chemist’s house to burn last!} To his friends’ astonishment, he whips out a giant buret, fills it with water and opens the valve. The fire is quickly extinguished, and all of the water used was exactly vaporized by the dying embers. The house and contents were saved! The neighbors’ congratulations quickly changed to gasps of horror as the chemist pulled out a match and relit the fire.

”What are you doing?!,” they cried.

”Reproducibility,” was his calm answer.

In a sense, the repeatability of experimental results can be said to lead to a hypothesis that is proved {almost} “beyond a shadow of a doubt.”

In contrast, LH proof is designed for what we techie types call a ‘singularity’—a non-reproducible or once-in-the-universe event. It is, by definition, impossible to make scientific proofs about a singularity, but they can be studied and information learned. It requires a different standard of proof though. That’s where LH proof comes in. As the name suggests, it is primarily the domain of lawyers and historians. “Who was the first president of the United States?” “What happened at the grassy knoll?” We cannot repeat these events, but we can gather evidence of all kinds that can point toward one or more conclusions upon which reasonable people can agree.

We’ve all watched the crime dramas. At the big courtroom climax, the defense attorney is making his grandiose closing arguments, performing for the jury. Then, in a sudden change of pace, he leans over the jury rail, looks each member in the eye and says slowly, confidently, “Today, ladies and gentlemen of the jury, I have proven to you that my client is innocent beyond [say it with me!] a reasonable doubt.”

So we see that the difference between a scientific proof and an LH proof is based on the type of phenomenon being studied. It leads to a difference in the burden of proof required. If a hypothesis-experiment pair is sufficiently clear, well defined, and well performed, then we tend to look askance at naysayers. They are viewed as not being all there or as folks who choose to disbelieve in the face of overwhelming evidence. (Take, for example, the Flat Earth Society.)

Confusion arises when scientific tools and methods are used on a singularity. Let’s say that for grins you developed a passionate desire to learn what I had for breakfast this morning. How would you go about trying to solve this dire mystery?

You might start by asking me. Simple enough. {Although, one semester when I posed this question to one of my classes, a student piped up, “Cut you open!” I replied, with tongue in cheek, “Thank you. Here’s your ‘F’, and there’s the door.”} I respond with a straight face, “This morning I ate filet mignon, Russian caviar, champagne, and finished it off with a splendid Havana.” You seriously doubt this, especially after learning my university salary from an Open Records request. What might you do then? You simply have to know what I had for breakfast.

Ask the folks who ate with me. They confirm my story. You, being an Oliver Stone protégé, suspect a conspiracy to hide the truth of my morning’s meal. What now?

Time to pull a CSI. You sneak into my house, turn out all the lights, turn on a flashlight, and examine my trash, my refrigerator, my kitchen sink, et cetera. Ah, but I am one step ahead of you! I have taken out the trash and put it in a dumpster 10 miles away. I’ve done my dishes, burned any receipts, cleaned the fridge and bleached the disposal. This only reinforces your need to know. Time for desperate measures.

You arrest me, haul me to a hospital and apply scopes to one end or another. I object, but you ignore me. My gut is pumped from both ends, and the contents analyzed. I had a breakfast taco. Hold the presses!

In your efforts, were scientific tools used? Sure. At the very least, the analysis equipment at the end would be considered scientific tools. Have you scientifically proven what I had for breakfast this morning? No. The event, ‘breakfast this morning,’ is a singularity. It cannot be repeated. Therefore, you have made a legal-historical proof.

If you wanted to know what I have for breakfast as a rule, you can observe me for a period of time long enough to see what my meal patterns are and develop a statistical model of my breakfast habits—78.2% of the time I have nothing (proving intelligent people can make stupid choices), 10% of the time I have Slim-Fast™, 9.6% is a breakfast taco, and so on. Yet this is still not a scientific proof, because there is not a repeatable set of conditions. Yes, each time it is morning, but that isn’t the only variable that affects the outcome. This kind of proof, known as statistical proof was mentioned earlier. However, we will not cover it any deeper here.

In summary, it is important to understand what type of proof is appropriate to answer the given question. But does that mean that all of science leads to scientific proof? If only it were that simple! (But then, of course, you knew I’d say that.) Take astronomy, for instance. Can you reproduce a supernova? No. (Chances are that you wouldn’t want to either! I hope.) How then do we study supernovae? We study records of observations made by others, turn our telescopes to those areas of the sky to see what’s left, etc. If we are lucky enough to observe one, then we make those observations. Based on what is learned, we then look for other areas with similar properties and try to determine if one has happened in the past or if a given star is likely to undergo one in the future. This leads to a body of evidence that describes what we know about supernovae. Therefore, conclusions about them are based in a legal-historical type of investigation.

Granted, this is a very simplistic discussion of the concept of proof, but it is a good starting place.


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