Probability is probably not real

For a moment, let’s think about the weather. Today, the weatherman is calling for a 40% chance of rain. What does this truly mean? It either is going to rain or it isn’t. Turns out that “chance of rain” is actually just a measure of the weatherman’s confidence that it will rain within a certain time frame in a given area. That’s it. Just someone’s level of confidence in a judgement.

We can apply this to other scenarios – say a coin flip. 50% chance one way or the other (hypothetically). In reality we know that the weight variability of the coin’s sides will skew it slightly towards H/T. But let’s think deeper. What else might skew the probability of heads v. tails? Well, pretty much everything. The initial conditions – angle, force you launch it with etc., air currents, particles in the air, objects in the trajectory currently and within a brief timeframe projecting into the future before the coin lands. The list would go on infinitely to the point that we surely could not account for every relevant variable in determining the coin’s outcome. So we model the outcomes with probability. But this probability has no actual bearing on the real outcome. In the same way that 1 inch does not exist, or 60 seconds does not exist, but the amount of space/time they measure does exist. Probability is the same way. It’s a concept we project onto reality to organize and understand it, not anything inherent to reality itself.

Probability is a way of measurement. And what does it measure? Confidence. If we say we are 90% sure of something, this doesn’t mean that we are 90% correct. We are either correct or not, certainly, one way or the other. The 90% just measures our confidence that our belief matches with reality.

Reflecting deeper on this, we realize that it is nearly impossible for us (as English speakers) to think in non-probabilistic terms. We simply do not have another word for it. If I hear a strange noise outside, I might say to myself something like “it’s probably a serial killer” or “I bet it’s bigfoot” or “most likely it’s my ex-wife.” All these statements really just mean that, in a scenario where I cannot know something with certainty, I have some level of confidence that my read is correct over the other possibilities. This evaluation will be based on historical data I’ve collected, which is then projected into an uncertain future to give enough confidence to justify a certain action. Just like the weather report.

When faced with patterns too complex to comprehend, we call them random. So what does this mean for the current model of quantum mechanics? I’m uncertain. But it’s probably not good.