Thread

1. creativeSlumber · 1790580636 · focus · HN ↗

   How relevant is this fast/slow thinking thing with regards to current frontier models?

   I know a large organization who's built their AI framework completely around this concept, and I feel that it's not really meaningful concept with the capabilities of current models.

   1. Retric · 1790582220 · focus · HN ↗

      You can ask a model for output directly and stop, or you can recursively ask it to keep refining the output.

      That seems to fit the fast vs slow model of human thought reasonably well.

      1. usernametaken29 · 1790587118 · focus · HN ↗

         > You can ask a model for output directly and stop

         That’s still several orders of magnitudes too slow to fit fast vs slow. Think of 30ms vs 3-4 seconds to get an idea of what we’re talking about here

         1. Retric · 1790587655 · focus · HN ↗

            That’s a function of the amount of processing power involved not the underlying architecture of decision making.

            1. usernametaken29 · 1790591813 · focus · HN ↗

               In terms of making an LLM faster but not in terms of meta-cognition. System 1 thinking as defined by Kahneman doesn’t have 100000x more compute than System 2, it is actually the opposite. That completely contradicts your claim

               1. Retric · 1790600944 · focus · HN ↗

                  The ratio between a single pass and multiple passes is unchanged when you throw more processing power at both.

                  In a human 30ms vs 3-4 seconds is a 1:100 ratio. Single vs multiple passes with an LLM varies but a 1:100 ratio isn’t unrealistic. So with enough compute and the right workload single vs multiple pass LLM could sit in that exact same 30ms vs 3-4 second timeframe.

                  1. hoppp · 1790605840 · focus · HN ↗

                     Multiple passes doesn't make it system 2. The defining characteristic of system 2 is consciousness which is expensive and slows down the system.

                     So to talk about system 2 in AI we need to talk about consciousness. As long as AI is not officially conscious there is no System 2 thinking implemented

                     1. Retric · 1790616213 · focus · HN ↗

                        Consciousness is ill defined hogwash when used in such descriptions.

                        The process of internal refinement without external action however fits.

                        1. hoppp · 1790619639 · focus · HN ↗

                           Using system 1 and 2 for AI is ill defined hogwash indeed.

                           The systems apply for humans and describe conscious and subconscious processing. Without that the entire reference to thinking fast and slow is bullshit.

                           1. Retric · 1790622703 · focus · HN ↗

                              System 1 and 2 is a description of physical process in people.

                              Using conscious vs subconscious processing is not however a meaningful definition. Subconscious processing isn’t necessarily fast. Visual processing and sensory integration can be quite slow without any conscious input.

                              1. hoppp · 1790687584 · focus · HN ↗

                                 Not all subconscious processing is fast, for sure.

                                 But for example the amygdala is super fast at tagging dangerious situations with emotions.

                                 And humans socialize subconsciously, so all the small talk conversations are all subconsciously generated.

                                 The definition from the book was:

                                 System 1 is subconscious, fast, automatic and relies on heuristics

                                 System 2 is conscious, slow, deliberate and effortful

                                 1. Retric · 1790709822 · focus · HN ↗

                                    The amygdala isn’t particularly fast here. It’s got significant connections to higher order centers in the brain and it’s own memory because classifying dangers let alone more complex emotional states can be quite complicated.

                                    If he’s defining System 3+ then that kind of specificity could still work, but from what I understand he doesn’t thus making subconscious a poor fit for the systems described.

                                    1. hoppp · 1790799764 · focus · HN ↗

                                       Reaction to danger must be fast, otherwise the animal dies.

                                       Saying that danger classification is slow is very clearly false because animals must react fast to danger or die.

                                       You bringing up something bogus like system 3 makes me think this conversation is pointless and Im just chatting with a system 1 that does not have good shortcuts to have a good conversation about this so it's making new up contexts.

                                       1. Retric · 1790810136 · focus · HN ↗

                                          > something bogus like system 3

                                          These systems exist, if the author you’re referring to is unaware or unwilling to discuss major issues with their classification then that’s a hit to their credibility.

                                          Danger isn’t some universal thing, people are adapted to notice fact moving objects heading towards them quickly very fast. A very dangerous snake isn’t in that category of danger and can take a significant chunk of time to notice after you’ve stopped looking in that direction. Noticing social danger is extremely critical and glacial by any of the metrics previously discussed.

                                          Emotions cover a huge range of complex interactions that depend on many different parts of the brain but hormones are inherently slow to diffuse through the brain. Pair bonding between a mother and child needs to happen, it doesn’t need to happen in 50ms.

                                          1. hoppp · 1790811195 · focus · HN ↗

                                             Yeah, pair bonding doesn't happen instantly but thats also not about processing and reacting to signals, it also involves the endocrine system as you say, so it's not an information processing system in the same sense.

                                             If a tiger attacks you, you better react fast, but one strictly human example is noticing and reacting to angry faces.

                                             An angry person comes at you with a bloody hammer you react before you understand what's even happening

                                             1. Retric · 1790814414 · focus · HN ↗

                                                > thats also not about processing and reacting to signals > not an information processing system in the same sense

                                                I can only assume you have some sort of philosophical objection here, but this is information processing.

                                                Neurons are reacting to a range of chemical signals not just a single neurotransmitter because they don’t map to what CS style neural networks. Understanding the brain requires understanding the nuances not simplified models.

                                                1. hoppp · 1790879971 · focus · HN ↗

                                                   I think it modulates information processing, the endocrine system does deliver information but it's internally recieved.

                                                   The key word is modulation.

                                                   Thats why I would not add the endocrine system as a system 3 or whatever.

                                                   DNA copying is also an information processing system but it's not considered in cognitive psychology but transcription factors will greatly effect behavior also.

                                                2. hoppp · 1790880131 · focus · HN ↗

                                                   But in the case of rats I would agree, their brains have more advanced olfactory systems and they communicate directly via pheromones to each other using the endocrine system.

                                                   But it humans that processing is more nuanced and the olfactory system is less advanced.

               2. pixl97 · 1790606318 · focus · HN ↗

                  >System 1 thinking as defined by Kahneman doesn’t have 100000x more compute than System 2, it is actually the opposite.

                  When are you measuring?

                  Systems 1 thinking is closer to precomputed tables in some ways. That is by evolution or massive amounts of training your neural network has a narrow fast path it can execute with as little compute at execution as needed.

                  1. Retric · 1790616381 · focus · HN ↗

                     Slower paths means loops here for humans where the output of a neuron gets feed back into itself. The fastest path = a feed forward neural network without loops.

                     LLM’s operate strictly feed forward neural networks.

                     1. usernametaken29 · 1790645438 · focus · HN ↗

                        Your assumption is wrong. Unlike artificial neurons, real neurons process massively and concurrently, let’s say 10-20 thousand inputs at once in less than 1 millisecond. In Kahnemans theory system 2 always involves the anterior cingulate cortex and arises when there are multiple conflicting streams of information. That’s the defining characteristic. Both system 1 and system two process in the same way, including looping back to previous areas. So really, no, stopping an LLM early vs letting it run has nothing to do with Kahnemans theory. In general LLMs are so far removed from what we consider natural cognition that it’s very hard to apply neuroscience concepts to LLMs simply because they share no real world similarity. At best, you’re simulating something in a very inefficient way.

                        1. Retric · 1790650165 · focus · HN ↗

                           We’re talking about biological processes which have physical limitations on how frequently a neuron can fire as well as a signaling system that based on how rapidly neurons fire. Loops anywhere in the system enforce a minimum 5ms latency and more realistically several times that. A typical neuron is firing closer to 0.1 to 2 times a second. Add to that the physical transmission speed and rapid response doesn’t allow for loops.

                           There’s a reason reflexes for the feet are handled by the spine that’s got nothing to do with total processing power.

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