100% Absolute Certainty
The universe is an incredibly complex place. At any given moment there will be more actions taking place universally than a human mind can possibly comprehend. Add to this, even the most advanced computer simulation will not be able to predict with absolute certainty the outcomes of a given situation. Things are just too complex, there are too many variables, there are factors we may not take into consideration, and there is human error; all of these factors can change the outcome of a situation being tested.
Even daily occurrences cannot be predicted with absolute certainty. There is enough going on outside of your control that you can’t possibly know for absolute certain that your plans for the day will pan out as you want them to. For instance, let’s imagine that every night before you go to bed you set your alarm for six in the morning, with full expectations that it will sound giving you enough time for your daily constitutional and to arrive at work on time. But maybe a storm cut power to your house while you were sleeping, the cat kicked out the cord from the wall socket, or maybe you went to bed late and slept through the alarm. To your mind when you went to bed there was no reason to suspect that any of these things would cause you to be late for work. In any case, the certainty you had that you would get to work on time turned out to be outside of your control. If you had known all the variables in advance, you may have been able to take action to avoid being late. But there is no certainty there, there is only reasonable expectations based on expected reasonable occurrences.
These occurrences, while unlikely, are much more likely than waking up to find that your cat had turned into a pumpkin, or waking up to discover that while you were sleeping that you morphed into a cockroach (as happened in the Kafka story “Metamorphosis“); that is so unlikely that we could label it impossible, within reason. And you could say with a reasonable level of certainty that you will not wake up in the body of an insect. Has something this ever happened before in all of human history? Outside of the Kafka story, I’d say not. And with this in mind, some things are more likely than others, and this should give us a basis for the level of certainty we hold about given situations. The more spurious the claim, the lower the likelihood that it is true, and the less certainty there should be given to this claim.
If however a friend told you that they’d woken up one morning to find themselves in the body of a giant cockroach, and that they still inhabit that form, although it is clear to you that they are in human form, you would tell them that maybe they should seek help for their obvious delusion. Perhaps medication and counselling would assist with their problem?
But these kinds of unliklihoods can be written off as impossible, there is no precedent for them, no known way they could occur, and are far more likely to be the product of an ill mind than the laws of the universe conspiring together for this outcome.
While the ridiculous situation outlined above may seem too far fetched to even be worth consideration, claims of this sort are made regularly and with apparent 100% certainty by people who believe in the literal interpretations of the holy books. Water, which has no grape juice in it, can turn to wine, and bread made from wheat can somehow turn into a complex living organism in the form of a fish. In fiction, things like this can happen all the time, but in reality, the world we all inhabit physically, these things are not only very, very unlikely, but are so unlikely to occur that we label them impossible.
In science, outcomes from experiments may vary from time to time, but there is a level of predictability that can be ascertained by repeating the experiment. The level of variation in outcomes is not as great as in the Kafka example, but there is some variation. Through controlling the environment of the experiment (sterile equipment, removal of anything that may interfere with what is trying to be measured), persistence and repetition we can arrive at a reasonable level of expectation of outcomes, but 100% certainty of outcomes is not one of them. There are simply too many variables for every possible factor in the universe to be taken into consideration.
There is even an entire physical principle which hinges on uncertainty. Heisenberg’s Uncertainty Principle shows that within quantum mechanics, “the more precisely one property is measured, the less precisely the other can be controlled, determined, or known.” (from Wikipedia) This has been a fundamental discovery in the understanding of quantum physics and quantum mechanics.
The recent “faster than light neutrino” claims coming from CERN, which instantly drew skepticism from people in the scientific community, for it went against the accepted laws of physics. As it turned out, it was too good to be true, and the results of the experiment could be blamed on a faulty cable. In this case, something too good to be true was in fact false. This skepticism from the scientific community shows fact that a single result is not enough to make something factual. And note, the results coming from CERN were not announced as “absolute proof of faster than light particles”. Rather the question was posed based on the fact that further testing was needed. If in fact we do discover that a particle can travel faster than light, it will not be decided by one single test, rather from many tests.
Uncertainty is part of reality, part of science. In fact, if it weren’t for uncertainty, mankind would never have asked what was beyond the next hill, why we stick to the ground instead of floating away, and what is beyond the stars. It is the uncertainties about our existences that keep us moving forward. Without uncertainty, we would still be stuck in the Dark Ages courtesy of the apparent “certainty” that religion offers. Religion placates the uncomfortable doubts about our existence and the nature of the finality of death by replacing them with the “certainty” of the existence of God, heaven and the afterlife. There are no worries, then, of doubting the purpose of your existence.
Benjamin Franklin is often quoted as saying “In this world nothing can be said to be certain, except death and taxes.” I’d like to add a third, that a person claiming absolute certainty is certainly deluded.