Predicting the Leaf

Is everything in the universe predetermined (predictable in theory) – like in a computer program?

Consider that all possible physical actions, whether atomic, subatomic, quantum, mechanical, electromagnetic, etc. are reactions. Let's emphasize that all physical actions are re-actions, and thus, hasn’t every physical reaction been predetermined?

Suppose the workings of the human brain were nothing but physical reactions. If your brain were nothing but physical reactions, then because they were re-actions, must your every choice have been predetermined?

Suppose you were born in 1950, and Starbucks were created in the 1970's, and you bought a particular coffee at a particular Starbucks at a particular time in 2010. Then, because your brain, every brain, and the universe, were nothing but physical reactions, would your purchase have been predetermined in 1950? Was your birth date a limitation on predicting your choice? Wouldn't your mother's and father's choices have predetermined your birth? Wouldn't all human decisions have been predetermined thousands of years before those humans were born?

Let's consider a parallel example.

If the universe were nothing but physical reactions, then hasn't every physical reaction been predetermined from the beginning of the universe? Wasn't it predetermined that a particular leaf would grow? Wasn't the leaf predetermined before the tree existed? Wasn't the leaf predetermined before that species of tree existed? Wasn't the leaf predetermined before that planet existed?

Instinctively, we feel certain that the particular leaf was not predetermined. Likewise, we feel certain that our choices were not predetermined.

However, we demand the concept of free will to explain why the physical reactions in human brains do not predetermine a particular choice. Whereas, we demand no concept to explain why the physical reactions of nature do not predetermine the particular leaf.

This thought experiment thus reveals a widespread cognitive dissonance in our thinking. Why must we project magical qualities into the physical reactions of our brains to explain why our choices are not predetermined? If physical reactions contained randomness, then randomness alone would make nothing truly predetermined.

A clever person would claim that maybe we can predict the leaf because we do think of the results of physical reactions, like a falling object, as being predetermined. However, predictable physical reactions are predictable only when two conditions are met: 1) we have isolated an event from all of the preceding reactions (the input) that led up to that instant in time, 2) it occurs on a scale that would overcome any effect of randomness, and 3) we are only predicting the next instant in time. For example, a 1000kg block of steel resting on top of an egg centered under it would definitely crush the egg when released. Even human choices can be pretty predictable when a large scale physical reaction is imminent – like stepping out of the way of a moving car. However, we don’t even know what will happen next. For example, which way would each egg molecule squirt?

A clever person would claim that maybe we can predict the leaf because we consider physical reactions such as the choices (the output) in a computer simulation, or even in any future artificial intelligence, to be predetermined when given known inputs. However, predictable physical reactions are predictable only when three conditions are met: 1) we have isolated an event from all of the preceding reactions (the input) that led up to that instant in time, 2) it occurs on a scale that would overcome any effect of randomness, and 3) we are only predicting the next instant in time. Considering randomness first, we have designed computers to have a very high probability of behaving predictably. We could have made the same computer circuit designs smaller, but then their behavior would be less predictable.

Considering the isolation of an AI choice is not as simple as it seems. While it is true that if we stopped an AI, took a snapshot of it’s data, and loaded that data onto identical hardware, then the two systems would perform the same next step; however, that next state (choice) would only be the next nanosecond, so we would have accomplished very little for our effort. To actually be able to predict the future choices of that AI, we would have had to load its data onto a faster (but otherwise identical) computer, and we would have had to guarantee that they both received exactly the same input (the same life experiences, saw the same things from the same angles, got the same reactions from other sentient beings, etc.), and that the faster one received that same input twice as fast (if the computer were twice as fast). We would thus need two planets starting in the same state, but with everything happening twice as fast on one.

The impossibility of predicting AI would be even more difficult with human brains because human brains are not identical hardware and because they are like a computer that has trillions of processors (instead of one) all processing at slightly different speeds and all changing their speed randomly. Also, human brains were not designed to eliminate randomness. Therefore, even if there were no such thing as randomness; the only way to predict human choices would be if our entire universe were an isolated simulation and another simulation started from the same state and were running on faster (but otherwise identical) hardware.

Note that software can emulate any physical process, so if we cannot yet model the workings of the human brain, then that is only because we do not yet understand the workings of the human brain.

Just as magic is not the reason that predicting the leaf is impossible, magic is also not the reason that predicting a human choice is impossible. The reality is that there is no magic. Once we understand reality, we are free from superstition, and once we are free from superstition, we have a greater incentive to start thinking for ourselves.

Freedom is the Promise of Reality.