Monday, January 05, 2009

Bigger Brother

The brain is the engine of thought and action, and the brain is entirely physical. Imagine that our understanding of the laws of physics evolves to a state that we can accurately predict how people's brains will react, and thus how people think in response to events in their environment. Such a machine is Pierre.

A brain scanner maps the brain states of a person. Then the supercomputer Pierre, monitors the various stimuli the person is exposed to and will then predict what their future behavior will be. But there are limitations. This technology works best in a controlled and enclosed environment akin to a lab experiment. And therefore the predictions can only be made a few moments ahead, since tiny errors in predictions escalate to large ones. But the computer can nonetheless predict how the person will react for the next few moments. In a sense we will be able to know the person's mind better than they do themselves. (Source: The deterministic thesis of the French mathematician Pierre-Simon Laplace)

When I read this scenario in the chapter, I was unsure of what the main questions/issues it dictated for discussion. The possibility of such an evolution in the world of science? The ethics behind using such a powerful technology? The implications on what the mind is, if it could be dissected so clearly by science? Is it a violation of some sort? Does it mean we humans are reduced to machines who can be predicted through their inputs? Is our free will, or ability to act as free agents, being threatened in some way if such a machine could exist?

To begin with, do I concede to the possibility (at least theoretical) of such a machine? Well, my knowledge of quantum physics is little to none, so I don't think I'm qualified to argue either ways. So for the purpose of this thought experiment let me assume that there can be such a machine; I take Laplace's word for it :) . Well then if the machine could predict our next state based on the physical states of our brain and environment, then does it mean our thoughts are no more random than physical causal events in the universe? Does it imply our actions are not entirely free, they are obvious consequences that we follow through with?

Well, I was thinking of the difference between prediction and freedom/free will, and the relationship they have between each other. It took me to astrology... then to destiny... and then to a wall :). An age old question again. Are we in control of our lives, or is everything "predestined", "meant-to-be" and hence subject to prediction based on our physical states? I seem to be asking more questions than try to answer them :)

Ok for one, the machine can only predict the next state lasting a few moments into future, not more than that....and that too in a controlled environment. Life is not really a controlled environment. And I don't know what sort of predictions on future actions/behavior the machine can make. Is it something as precise as "the person will now occupy the red chair, five seats from his right?", or something with a tinge of conditional probability stating "the person will likely drink water since it was hot out". If it were similar to the latter, then I don't see it as a threat to free will. All of us can predict and judge our close ones on their likes and dislikes, behavioral patterns, and can make predictions on the food they would order, the clothes they would buy, their reactions to situations etc. It doesn't mean they are stripped of their free will, their freedom is intact. They eventually choose to do what they want to. There will be a margin of error in our predictions. But if the prediction were as precise as the former, then it is surely unsettling. If it were based on behavioral and psychological patterns then it's not as alarming... for that's what psychologists aim at (although they would still account for a margin of error)

Why is it unsettling - 1) one is the fact that all these predictions were made not based on psychological attributes, but on physical states, 2) there is probably no margin of error in the prediction lasting to the next few moments, 3) there is seemingly no logic to some "random" actions... we ourselves wouldn't know why we decided to sit on that specific red chair to the right. It was random, yet a machine could attribute some sort of "causal link", 4) there is no real uniqueness to our thoughts and actions. It all would depend on neurons firing away based on the physical state of our brain.

So yes, I do see ourselves as predestined agents with a disillusioned sense of free will if there could be a machine predicting even our seemingly random actions with a high degree of precision, all based on physical brain states. It doesn't matter if the prediction is only valid for the next few moments; if there were some feedback loop, then the machine can continuously predict our next states in consecutive small intervals. But if the environment were too controlled so as to drastically cut down the choices normally available in real life then the predictions have a higher chance of being mathematically accurate, and they seem to lessen the severity of the threat on free will; not convincing enough to disregard the threat.

Now taking a slight detour - I am curious about what one's belief in destiny is. There are some who take comfort in the knowledge that their lives are destined and set. Failures are not seen as harsh since they resign that no matter how hard they tried there was a greater force that they couldn't alter. Their actions are hence not blamed as much, they seem to cope up with changes in life, and are resilient to adapting since they accept each turn of event as the work of destiny. On the other hand, are those who can't accept that their lives are being controlled in some manner. They want to be in charge of their lives, and cringe from the possibility that their actions are not entirely their free will. And some in the middle, who view a little of both happening. I sometimes think Life is a game similar to Monopoly. There is an element of chance/luck due to the throw of the die. But once we reach the spot, what we choose to do at that juncture is up to us, our free will.... although our choices are very limited due to the rules. Who framed the rules of Life? Many times society, many times we ourselves.

Update: I just came across a wonderful post here: where the author has done a good job of bringing in the perspectives of determinism from the standpoint of Laplace, Heisenberg and Einstein. It adds the much needed physics-dimension to the discussion.


SUMI said...

I am really not sure what to believe with regard to determinism and free will in our lives. I do find the idea that our lives are predetermined unsettling. I had similar thoughts, and thoughts about similar ideas - check out this post when you have time:

SecondSight said...

Lots of interesting ideas here! Being a biologist I'll focus on the first half alone.. :) - A machine that predicts short-term futures based on brain patterns isnt' really that hard to imagine. I'm not much of a neuroscientist, but if you consider Pavlov's experiments, and the basis of memory and associations in the brain, then its' not very hard to do. All you would have to do (theoretically)- is to identify which neuronal connections were stronger than others, and to what extent- it then just reduces to a probability-based mathematical model (a very complex one.. but still, its just numbers) to figure out what a person's next thoughts/ moves are likely to be!
Belief in destiny/free will etc would come down to a mind-brain connection... no comments there !:)

Neeraja said...

Sumi - Thanks for pointing me to your post! It was a wonderful read :)

Second Sight - Thanks for bringing in the perspective of a biologist :). But in my understanding, Pavlov's experiment is on behaviorism; that which considers response to stimuli (behavior) through series of observations and then comes up with an understanding of behaviorism. One of the major criticisms is the behaviorist's neglect of what happens between stimulus and response (i.e., inside the brain, the neurons and the explanation of how thought is converted to action). Such behaviorist predictions were based on observation of behavior *after* administering the stimuli, and besides not on physical brain states.

I guess I'm not sure how one can determine stronger neural connections before exposing the stimuli. For example, when I enter a room I have little knowledge of the exact things I would do. When i see the room and take in the stimuli (chairs, tables, people etc), my neurons start firing at that instant, connections grow stronger and before the few milliseconds when I actually take an action, prediction might be possible. But can prediction be possible even before the exposure of stimuli?

Before I enter the room, I may want to sit near the speaker, and those neural connections might be stronger. But I may have no clue that there would be a huge fish tank inside the room. Knowing me, if I were to enter the room, one can expect those neurons to fire more strongly that drive me towards the tank, rather than towards the speaker :)

Neeraja said...

Second Sight - And that little tit-bit about mind-brain connection!! Aaah... i'm itching to know what u mean!! :)... u mean something to do with dualism or functionalism?

SecondSight said...

I'm going to conveniently answer only your first question for now ;) (the rest when I'm not doing RNA preps :)) - Pavlov's experiments were on behavior.. but memory also plays a significant role here. How does your brain know what the fish tank is, and how did you establish your preference for the fish tank vs. the speakers? The answer most likely lies in your past exposure to one/both of those. And that exposure is 'stored' as your memory- in chemical and biological terms in the brain. The actual machine that can measure the differences in quantities of chemicals, strength of a synaptic connection, etc.- I'm not sure how close we are to making those systems, but theoretically- if you could say that ten molecules of chemical A in the fish memory vs. eight molecules of A in the speaker memory imply that you like fish more... Shouldn't that help to set the principles for the construction of such a machine?

Neeraja said...

Thanks for the prompt reply! :) And I'll be waiting to hear more of the second question when you find time :)

Of course there will be memory associations, but what if I have never been exposed to a fish tank and an important guest lecture both at the same time? I agree that the principle starts off as logical, but the actual predictions and their accuracy depends on the extent to which I have been previously exposed to all/combination of stimuli being tested on me. Maybe more complex mathematical models will be in effect.

But this puts me at ease. I wouldn't call this as violation of free will... my free will circles common patterns, easy enough for a machine to predict :)

I'm curious how the machine would predict a child's actions... no set patterns, seemingly random and spontaneous actions.

SecondSight said...

Good morning!:) To segue from this discussion to the second point- When we use the term "free will"- do we emphasize the "free" or the "will" ? If it is 'freedom'- then as multiple instances prove, no machine (or human being) can completely control your freedom- Galileo and that small fraction of Milgram's students stand testimony to that ;). If it is the 'choice' that we focus on, then who is it that 'wills' actions? Your mind or your brain? And is it possible for one to over-ride the other? How much of psychology has a physical basis, and where is that physical basis- in the brain,or in every cell of your body? For example- you have been taught from childhood that fire can burn. So when you singe your fingers on the stove and pull your hand back, it is a reflex action, involving no higher brain power. Now imagine a scenario where your favorite book/person/fish is in danger of getting burnt. You jump in to rescue them. CNN would attribute the heroism to your emotions/ hormones- but at some point, the 'mind' in your hands was overtaken by the synapses in your brain..
So, mind-brain-body connections ?:)

Neeraja said...

Second Sight - Thanks for elaborating on your previous comment! :)

Well, I'm not worried about a machine completely controlling our freedom. My consternation is that if our actions can be so accurately predicted based on physical states alone, isn't it just as similar to predicting a snow storm based on the physical states of the environment? And just as a storm becomes inevitable are our actions obviously inevitable no matter what we "will"? Then it seems like we have a false sense of our freedom and what we "will", for ourselves.

Regarding the mind-brain-body connections and how much physical basis psychology has - that's a wonderful question. It really does get us down to the root of it all :). There are many theories on the philosophy of the mind - physicalism that argues there is only a physical state and everything has a physical manifestation (including mental states in the form of neurons firing), dualism that separates mental states from physical states, and functionalism that identifies mental states as having functional roles in response to other mental states and behavioral outputs. For now, I orient more towards dualism than the other theories :)... I do believe there is a non-physical entity called the mind, and consciousness is a part of it. Functionalism is convincing enough a theory but it doesn't convince me enough on how consciousness gets defined/functionally specified.

In my view the physical basis of all thought originates in the brain/neurons, not on other cells in the body. But desires, feelings and beliefs from thoughts originate from the mind, since I'm more of a dualist :). And from that follows that interactionism (physical events generating mental events that interact with the physical state to execute corresponding actions) intuitively makes more sense to me than epiphenomenalism or reductionist principle.

But now I see that if a machine could predict future states based on neural connections alone, then that seems more like a reductionist's concept, eliminating the "mental states" from playing a role in the actions performed. I'm not comfortable with that, yet there is no way I can prove it right or wrong :)

Can the mind/brain override one another? I don't think so... there is constant interaction between the two; Interactionism has it's own weaknesses in explaining the causal link but it's the theory I agree to most closely :)

Anyway wrapping up... since I do believe in a non-physical entity "mind", I think that's where "free will" originates from, and the possibility of a machine predicting actions through physical states in the brain alone seems to render the "mind" as being insignificant... thus rendering free will as an illusion.