Uncertainty Part I: Nothing is Sound
Several years ago I woke up feeling very strange. Stranger yet, that description of “strange” was the best I could do to explain it. I felt strange. Sure, my stomach was oddly tight but I wasn’t nauseous or dizzy or in pain. I simply felt completely disoriented. I asked myself a few questions. Who was I? I knew my name (at least I was pretty sure I did) but if my brain was off kilter how would I ever know? All I had to check my brain with was my brain. Where was I? The hospital. I knew the room number, the floor, the name of the hospital, the city, and why I was there. I just didn’t know how I came to be waking up in this position feeling like this. Some of my personal history was missing or, worse yet, clearly unreliable. I knew I had not vomited on a presidential candidate during the night but had I had a chest x-ray?
Eventually these questions all got answered. I had gone septic during the night and starting throwing up. The anti-nausea drugs all contained tranquilizers that had caused me to have strange, vivid dreams that were inseparable from my not-quite-waking moments when the doctors were talking to me but I was unable to pull myself all the way out of sleep. Also, I’d been pumped full of fluids stretching my skin out and causing me to weigh ten pounds more than I had when I went to sleep.
This level of uncertainty is both rare and extremely disconcerting. I don’t know anybody who likes to be seriously disoriented and my own experience of having to question the basic data which my brain was sending me was quite disturbing. However, the simple fact is that it is sometimes correct to be uncertain and incorrect to be certain. I deal with this issue most critically when it comes to the Bible. When should we be less certain that the text is clear and that we have the answers?
Nobody likes to be uncertain about critical issues and a lot of American religion is about certainty, something that has not escaped any number of mocking atheists. What I wish to do in this article and the next one is address the issue of epistemological uncertainty and how we deal with it.
My first point, the one that will make up this first article, is that we are fundamentally uncertain about everything beyond our own existence. Even that has a lot of caveats – you may exist but can you prove that you exist in the form which you think you do? Plenty of people claim to be famous people from the past and truly believe it. Other people claim to be non-humans and believe it. The Matrix famously played with the idea that our world is a construct of hostile machines. If you had a complete psychotic break with reality how would you tell? And since you can’t tell if your brain is lying to you how do you know that it isn’t right now?
Most of these big uncertainties are unimportant to our daily life. Sure, you can’t prove that you aren’t a bug-eyed tentacled horror living in a jar with a simulation of being human being piped into your head but what of it? Acting like you’re some sort of monster and that the entire world is a simulation just doesn’t produce any sort of measurably good results. You aren’t about to change your behavior just because there’s an off chance that your entire world is a lie. What’s more important are the small uncertainties. Let’s take your sense-data for starters. You generally believe that you see a clear picture of the world. In fact, the image you see comes to you as differential stimuli on three color channels and is spotted with holes and blood vessels. Your brain makes inferences about the world from this data to give you the clear picture that you are consciously aware of seeing. Optical illusions work so well because these inferences are imperfect and can be exploited. However, in everyday life you can be deceived by your own senses as well. On a simple level think about mishearing someone. You normally mishear someone saying actual words. However, to mishear them you almost certainly received garbled sounds that your brain then stitched together as words because it knew that you were being spoken to. This can go deeper, though. If your brain misinterprets things because it knows they are words but didn’t pick up any clear words, then could your brain hear words when there are none? Certainly. Play white noise to someone in a house which you’ve told them is haunted and see what happens. In fact, I had an odd experience with this bias some time ago when I conversed with a person who claimed to see bigfoot quite regularly. How was it that this person had racked up more bigfoot sightings in one year than are reported for most states (leaving aside the question of whether bigfoot sightings involve an actual new creature)? Well, he was either lying or, I believe more likely, his brain filters were set to tell him that every moving shape and every loud sound in the woods was a bigfoot.
A few months ago I was camping with some friends and two of us went walking along the trails after dark. We began talking about scary incidents in the woods (he had a good selection of such stories) and then, suddenly, he said, “I see something moving back there.” Sure enough, two glowing green eyes stared back at us well off the ground. This was no fox or raccoon. Eventually we got our lights trained just right and illuminated a deer staring back at us but for those first few seconds the eyes seemed to be anything. I at least had my brain filter tuned to “scary things” and it took a while to readjust.
Take another aspect of our lives. We all relate to people every day and in relating to them we have to reconstruct their mental states. However, we often get other people’s mental states wrong. Moreover, we’re likely to get them wrong in consistent ways. Imagine telling someone that the person they love is an embezzler. You’ll need good evidence to get past the initial filter that reinterprets the actions of people you like in a good way.
We build our worlds out of bits and pieces of data that we reconstruct with plausible hypotheses about how the world should be. People should be speaking words, things in areas that we frequent should be recognizable, people we care about should do what is right and people we think of as bad guys should be up to no good. At every layer from the initial release of sound or light energy into a nerve cell all the way up to the construction of a mental model of the world we make inferences that are less than certain. We all know people who have created models of the world that are terribly askew. Are we sure that we are not such people?
The good side of this (and I’ll treat this more in the next article) is that we actually have a great deal of experience dealing with uncertainty. We think of uncertainty as unpleasant but we rarely find the uncertainty of our everyday lives to be awful. Uncertainty need not be feared because we already tackle it daily.