There are scientists who believe the knowable universe is just a program. You’ve heard of the game called the Sims? Imagine that on the scale of the entire universe.
There are those who believe that free will does not exist. If only you knew the exact position and momentum of every particle in the universe, you could know everything that ever has and ever would happen.
I take a hard scientific look and doubt that is the case. One example is quantum uncertainty. Quantum mechanics tell us that not only can we not know the exact position and momentum of a particle, a particle does not have such exact traits. Everything exists in a cloud and the act of measuring is what creates those traits. In point of fact, even if such exact traits existed, the act of measuring them inevitably changes them. At the very tiniest level of the universe, there is no objective reality other than what the observer creates. Quantum theory tells us the act of measurement changes reality, so we have a mechanism right there telling us the future is largely unknowable in detail.
If this were not so, modern applications of quantum theory would not work. Zeiner diodes wouldn’t work. Quantum encryption wouldn’t work. Quantum uncertainty even spells death for black holes, as it allows for them to slowly “evaporate” via Hawking radiation.
Chaos theory tells us that tiny changes in our model of reality can cause overwhelming differences down the road. The butterfly effect, where the flapping of a butterfly today can result in the creation of a hurricane in the future. (Conversely, mighty efforts made today can as easily fade to nothing.) Imagine if you will a perfect pool table, without friction. And equally perfect balls and cue. And the world’s greatest pool hustler trying an immensely complex trick shot. The slight errors introduced would make it impossible to predict what the table would look like after just a few collisions. Tiny errors don’t just add, they compound.
Sure you can predict at least that the table will still be there. For a while at least. The pool table simply has a much longer time scale than the balls.
Suppose we apply this to humans? Chaos theory tells us why we cannot predict politics or the weather or the stock market any real distance into the future. You cannot measure “now” accurately enough. Your prediction of the future degrades every time you try to push it further into the unknown.
A kind of human quantum theory would tell us the reality in our mind is just a cloud until the action of asking a question creates the answer. Ask it slightly differently, you get a different answer. The act of measurement changes what is being measured. Tiny changes from innumerable interactions cascade chaotically into vastly different futures. How do you predict the future from that?
Now to toss another log onto the fire. Gödel’s Incompleteness Theorem tells us that within any internally consistent logical system there must be statements that cannot be proven. In geometry, we’d call that a postulate, in algebra, an axiom. That which must be taken on faith, that which we must assume to be true but cannot prove, is called axiomatic. An example in Euclidean geometry is the parallel postulate: Given a point not located on a line, exactly one line passes through the point that is parallel to the original line.
Prove it. You can’t. Euclid doesn’t work without it, yet it cannot be proven. You take it on faith. And as it turns out Euclid was wrong and has been replaced by Einstein and N-dimensional curved space-time. But Einstein, in turn, has his own postulates. Will he be overturned by a model that better fits reality? If he is, it will be another system that has its own postulates.
What Gödel tells us is that we must proceed with some level of faith or we don’t proceed. Much of humanity’s progress to date has depended on faith, whether it be in parallel lines or in God or in the absence of God. Atheists have faith that “God” does not exist – as surely as the religious who believe in God have faith that he/she/it does.
Let’s return to the beginning of this essay. Neil DeGras Tyson, astronomer and not known for his religiosity, thinks there is a 50-50 chance the universe we know is nothing but a simulation running on a computer. He is not alone among serious theoretical physicists. What would that say about the nature of God?
I rely on Occam’s Razor (the belief that the simplest answer is often the best) to escape from solipsism (the belief that I may be the only thing that exists). Solipsism suffers from “the problem of beginning” as much as any other philosophy. It is no more satisfying than assuming the perceived world actually does exist. To keep it simple, I believe that what I perceive is a reasonably accurate representation of the world around me. I understand there is a non–zero chance I might be wrong. I simply discard the chance from my equation of life because it isn’t useful. I suggest you do so as well.
Of course, none of this explains how I can be happy or why a magnificent sunset moves me. I suppose that will be a different post. It does show why faith is necessary, even inevitable. Why I think free will and choice matter. It shows why the great movements of humanity are no more predictable than the weather. Looking back it is obvious why things happened but looking ahead is looking through a glass, darkly. It explains why I honor all traditions of faith equally. It is simply impossible to determine which one(s) (if any) got it right.
Just don’t try to force your faith on me. I’ll kick your epistemological ass if you try.