Sunday, 27 September 2015

What Lay People Should Know about The Scientific Method – The Investigative Process

by Zad Datu


Preceding related article (Read first!):
What Lay People Should Know about The Scientific Method – Hypothesis vs. Conjecture


If you read the previous article, once again, I would like you to forget all scientific jargon and imagine the same scenario. If you haven't read the article, imagine the following scenario:

One night I was in the jungle and a creature of significant size attacked where I managed to escape leaving only a scratch on my shoulder. I could not identify the creature at all. The following day I hired a team of investigators to solve this mystery. Following procedures, they developed a first hypothesis, that is the creature was a large dog. They obtained a specimen (dog) of average height and weight for its breed, get it to scratch piece of animal flesh, of similar composition to my shoulder and then compare that scratch mark with the scratch mark on my shoulder. The results shows that the scratches doesn't match.

Does this prove that the creature is not a dog?

The answer is 'No'. This does not prove that the creature is not a dog. It only eliminates the hypothesis that states that the creature is a normal adult dog of that particular breed.

What needs to be done next is to test all the breeds of dogs of significant size in the same manner. In other words developing many more contradicting hypotheses then test and eliminate them one by one. Upon the tests, results for all breeds of the proved negative. Again, this doesn't eliminate that the creature isn't a dog of any breed. This only eliminates all normal sized dogs of all breeds as the possible culprit. It could be a mutant over-sized dog, but lets not go there just yet.

Moving on to the second speculation, the 'tiger-hypothesis'. Here, results proved positive - the scratch matches.

Does this prove that the creature is a tiger?

The answer is 'No', once more. This only proves that the hypothesis which states that the creature was a tiger has not been eliminated. After all, when a lion is placed to the test, the results also proved positive as expected since tigers and lions have very similar shape form and size. The creature can't be both a tiger and a lion at the same time.

Now, we have two leads to follow, and most likely other big cats of similar size would test positive as well. But before going into that, lets try to figure out how could a big cat end up in that. One possibility is through animal smuggling. To find out if this is the case, we need to investigate on the industry of animal smuggling in this area. Lets forget about this for now. Another possibility is that the big cat escaped from the nearest zoo. Easier to investigate upon and seemingly more plausible the investigators dive into this first. The investigators have discovered that there are lions and tigers in the zoo. There are no records of escaped tigers.

Does this eliminate the hypothesis that the creature is a tiger?

Again, 'No', it doesn't. It only eliminates the hypothesis that the creature is an escaped tiger from that zoo. This does not eliminate the hypothesis that the creature is a tiger from other sources, perhaps animal smuggling. On second thought, this also doesn't eliminate that the record from the zoo is incorrect. But for now let us assume that the zoo record is genuine.

The investigators then discovered that there is a record of an escaped lion. The lion escaped 7 days before the incident where I encountered the creature. The investigators would now have to consult a lion expert to find out whether an escaped lion from the zoo is likely to find its way to that jungle and how long it would take to get there. If it takes less then 7 days for the lion to reach the jungle this hypothesis still stands. Whereas if it takes more than 7 days, this hypothesis fails. To put this story to an end let us say the creature turned out to be that escaped lion and that the investigators have discovered that part of my ripped clothes were in the possession of that lion.

Now, let us restart the story all over again from where the investigators were hired. Let us say that instead of developing the 'dog' and the 'tiger' hypothesis, the first and only 'hypothesis' the came up with was that the creature is a bigfoot. This was then seconded by another member of the team, then a third. Out of anonymous decision and without further ado they pronounced the mystery solved and case closed. The creature was a bigfoot, they concluded.

Obviously, this is ridiculous. Apart from that fact, not only were they not bothered to place their 'hypothesis' to the test, they did not even bother to identify whether it is a hypothesis or a conjecture, or whether the properties of their speculation were definitive and measurable, which in this case they weren't. We can't obtain a specimen of bigfoot to put it to the test since we never caught one, hence bigfoot is an arbitrary concept. The speculation isn't hypothesis. It is a conjecture.

Even if bigfoot was a definitive and measurable property, and the speculation is a testable hypothesis. The method of how the investigators come to consensus is simply unreasonable and irrational. This isn't a reliable method to use as a source of information to confirm the credibility of one's conclusion of the incident even if the conclusion just so happen to be correct.

Though one may think that this second retelling of this investigation is ridiculous, this happens every now and then in casual conversations within many communities. When a group of people witness someone experiences mysterious symptoms upon his stay at an alleged haunted house, or when a friend claims to see things that other don't see, or perhaps when oneself see things which others don't see, it is very common for that entire group to mutually agree and conclude on single explanation without any process of investigation with a generic and arbitrary term, 'ghosts', often speaking of their conclusions as if they are as credible as proven factual information.
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