For those who don’t know, “Occam’s razor” is a theory of problem solving attributed to a Franciscan friar by the name of William of Ockham, who lived about 800 years ago. It is usually interpreted, in layman’s terms, as “all things being equal, the simplest explanation is usually the best.” However, while many people believe this is a broadly accurate philosophy, the reality is that it may be less generalizable than commonly accepted.
Part of this may have to do with the interpretation: the more accurate translation is “among competing hypotheses, the hypothesis with the fewest assumptions should be selected.”
This is an important part of the deductive reasoning applied to the fields of engineering and science. The simpler engineering design, all things being equal, will be easier to construct, test, and maintain. The scientific hypothesis with the fewest assumptions will be more likely to withstand detailed analysis as those assumptions are examined. But what if those assumptions are untestable? Is a hypothesis with one untestable assumption better than a hypothesis with three testable ones? Or worse?
As an example, let’s discuss the topic of alien abduction. Let’s say that a person named “Bob” claims he was abducted by aliens. This claim could be tested by these three hypotheses: (1) that Bob is lying, (2) that the Bob thinks he is being truthful, but was really not abducted, and (3) that Bob was, indeed, abducted by aliens (or someone looking like aliens).
Now, in the absence of physical evidence, one could claim that the three above hypotheses probably meet the “all things being equal” criteria. So, what about the assumptions?
To test Hypothesis #1, we have to assume motive. So: can we prove motive for Bob to be lying?
To test Hypothesis #2, we have to assume that Bob (a) was in a mental state where he could not understand reality and (b) that mental state led him to believe he was abducted. So: can we determine Bob’s mental state at the time? If so, can we prove that something could have made him think he was abducted by aliens?
To test Hypothesis #3, we have to assume that (a) a space faring civilization exists that (b) has found us interesting enough to (c) want to abduct members of us to study and (d) can do so without being detected and (e) without leaving any physical evidence. So: can we test any of these? No? That means we can toss this one out, right?
By Occam’s razor, Hypothesis #1 should be chosen first to test, because it has the fewest assumptions. So, we do a background check and give Bob a lie detector test, both of which are inconclusive. Bob passed the lie detector test, and he is a model citizen with no obvious reason to be lying. So we move on to Hypothesis #2.
To test Hypothesis #2, we have to determine Bob’s mental state at the time he was allegedly abducted. So, we put him in a room with an analyst who, after much discussion, determines that Bob is of a sound state of mind. Also, medical analysis rules out any type of drug use, chemical imbalance, abnormal brain function, or any other physiological possibilities.
So, either Bob was temporarily hallucinating in an undetectable way that made him susceptible to perceiving he was abducted, or he really is lying. Or he truly was abducted by aliens. None of which, by the way is conclusively provable (or conclusively disprovable).
Oh, one other thing: during the background check, it was determined that nobody can account for Bob’s location during the time period he says he was abducted.
Thus, the results, using Occam’s razor, are inconclusive for this situation. We have no provable hypothesis, nobody wants to call Bob a liar, and he’s obviously not currently crazy. So, is Hypothesis #3 back on the table? Yes. Why? Because, while the assumptions behind the alien abduction theory are improbable, they are not necessarily impossible.
Consider this: we live in a universe that is billions of years older even than our planet and sun. Within that universe, there are billions of galaxies, with over 100 billion stars in our galaxy, alone, and those stars have planets. Lots of them, as we are currently discovering. And a not insignificant percentage of those planets are capable of supporting life as we know it. So, it is not unreasonable to assume, given the age of the universe, that some number of those planets have spawned intelligent life, and that those beings went on to create civilizations, some of which may be thousands (if not millions) of years ahead of us in terms of understanding the laws of physics. So, if there’s a way to break the speed of light and zip around the galaxy, ala Star Trek, then it’s probably safe to conclude that some enterprising civilization has already figured out how to do it.
Now, the coincidence of that civilization’s rise and fall overlapping with ours, and whether that civilization knows about us, and cares to send a mission here, and so on, only adds to the improbability of it happening. But, strictly in terms of Occam’s razor, it cannot be ruled out, because improbable does not mean impossible. The best we can say, given the above data, is that “Nobody knows where Bob was, and he really seems to believe he was abducted by aliens.” Anything else is conjecture.
Which brings me to my point. Occam’s razor is not a proof of truth. It is merely an effective means of trying to get to it. But until a chosen hypothesis can actually be proven, then all are valid. Even improbable abductions by aliens.