Tag: finding the truth indirectly

The Problem

Photographers have a mantra – “It’s all about the light”.  They can talk endlessly about what makes good light and bad light and most live for “the golden hour”, which is never actually an hour but occurs just after sunrise or just before sunset.  Most people don’t realize that there are photons

bouncing around at all times of the day and night, and if you put your camera on a tripod and leave the shutter open long enough you could make your midnight photo look like the middle of the day (albeit an overcast day, since there will be no shadows).

With all of this emphasis on the light, it is interesting to note that looking at most photographs gives you very little information about the source of the light, but a great deal of information about the subject of the photograph, which is reflecting light that it has (heavily) filtered from that original source. And so it is with most human intercourse. Politics is rife with examples. When your friend is ranting about Obamacare, which he or she probably hasn’t even read, you will invariably learn more about their hopes or fears than you will about any of the President’s policies. This is a fact of life that critical thinkers and skeptics routinely take into account.

How To Cope

Probably the most extreme example for discovering an indirect, heavily filtered truth would be the old logic problem of “The Island of Truth tellers and Liars”^A. In one of the various versions, there is a remote island that has two separate tribes. At one end of the island is a tribe of cannibals that always lies, while at the other end is a more civilized tribe in which everybody tells the truth. From a landing at the middle of the island, a traveler moves inland until he comes to the fork in the road leading to the tribe at each end. There he finds two natives, each in distinct tribal dress, but he doesn’t know enough to determine which native comes from which tribe. He asks the one dressed in yellow which tribe he is from, but doesn’t understand the answer. He asks the one in blue “What did he just say?” to which he gets “He said he was a truth-teller”. What did the traveler just learn and from which person should he ask directions to the civilized tribe?

If you’ve already heard this problem, you may want to skip ahead to the next paragraph right now.  The second of the above two questions is the easiest; the traveler has no choice but to ask the only native that he can understand.  The real question is “Can Ms. Blue be trusted?”  In this case she can be.  It really doesn’t matter that the traveler couldn’t understand the first native because the first question will always have the same answer.  If Mr. Yellow is a truth-teller, he will tell the truth; if he is a liar, he will lie about it.  Either way, he will always say he is a truth-teller, meaning there is no way to know the tribal affiliation of the first native.

 You can learn the tribe of the second person by comparing their answer to that known constant.  Since Ms. Blue accurately reported Mr. Yellow’s answer, it is she and not Mr. Yellow that is the truth-teller.  You may follow her directions when she points to the tribe of the truth-tellers.  Had she reported that Mr. Yellow claimed to be a liar, you would have thanked her profusely before heading in the opposite direction of her pointing finger.

Unfortunately, in this problem the most extreme case is actually the simplest to solve.  In real life, one’s truthfulness (or lack thereof) may not be as dependable.  In that case you must carry both possibilities in your mind until you have finally gathered enough evidence to rule one out.  Knowing the right questions to ask would be a big help, but all answers should be regarded with suspicion.

I realize that’s not much of an answer, but things aren’t always as simple as black or white.  If you were expecting simple answers to life’s hard questions, maybe you need to grow up.  But then again, I may be only scolding you to hide my own inadequacy in providing useful information.  That’s why it would be good right now to open this up to give my astute readers a chance to provide a better perspective to the problem.  (That’s your cue).  Thanks for listening.