mountains of possibility

sometimes twitter brings fodder for interesting conversation. I’m down on centralized social media a lot lately, but I’ve enjoyed it over the last 11 years, and still occasionally get some utility out of it. for instance, I happened across the following diagram:

tim urban's original tweet

it’s simple concept, but communicated beautifully. your life is a series of decisions, and at each point you are simultaneously closing off possibilities and going deeper on others. sometimes visualizations bring the point home and collapse the meaning into a smaller mental artifact than a long-winded description.

this concept rhymes with something I’ve been looking for a good way to communicate. one of the key differences between living things and non-living things the internal complexity which results in increased difficulty in predicting their future state. the moon orbiting the earth, while quite large, is not that complex. it is easy to predict its location far into the future. similarly predicting the future position of a person in the future is much harder, mostly due to our complexity as living things, but also especially due to our brains. a prediction would need to take into account our culture, calendars, social lives, and many other aspects that are hugely complicated.

the brain is way of packing an immense amount of complexity into our bodies, which maximizes the possible future states we can be in. without human brains, the possibility that we’d be located in buildings would be exactly zero. but with them, the possibilities may literally be infinite.

imagine a tall mountain. the peak comes to a point and the base is spread out over miles. now imagine a ball bearing, held directly over the highest point of this mountain, such that if it were dropped, it is equally likely that it would fall down the east face of the mountain as the south as the west as the north. so the location of the ball after dropping it could anywhere on the face of the mountain or at the based of it, spread out over a surface area of many square miles. sort of like a giant pachinko machine.

I use the imagery of the mountain to explain the immense complexity of the human brain, and it occurred to me that the image in the above mentioned tweet is a great analog. turn the branching flow sideways and imagine that at each branch point the ball strikes the mountain, the different paths taken represent the different angles at which the ball caroms off the mountain resulting in it taking different paths down the mountain.

in this mode of thinking, the path of the ball is determined by the drop, but known to the entity dropping the ball, only time playing out will reveal the actual course of the ball bearing down the mountain. this matches with what seems to be correct about human actions as well. there’s nothing about our actions that is undetermined by the physical matter that makes us up, and yet our brains are so complex that predicting the outcome with any specificity is currently beyond our capabilities. this leads us to the philosophical position on free will known as compatibilism. it is the belief that determinism and free will aren’t mutually exclusive. I think there’s a lot to be wrangled with there, and I’m not sure I sign off on all of it, especially without a detailed description of “free will”, but I do like the implication that complexity renders our actions currently unpredictable, which may be good enough to be thought of as a form of free will.

if you have clarifying thoughts or suggestions let me know, I’m interested in honing this line of thinking.