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The baffling intelligence of a single cell: The story of E. coli chemotaxis

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Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#221

Post by rajnathani »

jonnycat wrote: post #198

This kind of unicellular complexity & intelligence has long been my soapbox material in the AGI debate. Even long before the current LLM craze, people were counting neurons in the brain and making bold claims about machine intelligence - in just X years, we'll have a machine with the computational power of the brain! But of course, every neuron in the brain is bafflingly complex and we still don't know or understand…

Though, I feel that ANNs' number of neurons are under-represented is some ways:

- In the example case of a CNN, the total weights of a kernel is of [Input Number of Channels * Input Kernel Size * Number of Filters], which can be a pretty small amount when it comes to for example a 3x3 kernel with 3 channels with 128 filters coming to a total of 3,456 parameters (3 * 3 * 3 * 128), however in the case of an ANN the same filter is strided across the entire 2D input feature map (or 3D for 3D CNNs). If the input image is of HD resolution of 1280 * 720 and the stride is 2 across both dimensions, then the number of strides is 230,400. The effective number of parameter activations is 796,262,400 (3,456 * 230,400). The reason for this example is that it is sort of a known thing for likely decades now that CNNs are inspired in part by the human visual cortex [0]. For the human visual cortex which needs to be fast, there cannot be parameter sharing across a single kernel, and likely the weights would need to be parallelized to an extent, which would theoretically imply duplicating the weights across the human brain. Thus, the advantage out here lies with ANNs.

- The neurons in the human brain would have to have a certain level of redundancy in place due to the constant cellular repair work.

- The neurons in the human brain can seemingly only be updated by Hebbian learning rather than direct updates which is in the case of the computer memory of ANNs.

- Finally, a significant part of the human brain is for non-logical but environmental reasons, such as movement and touch, and non-logical things such as fear, jealousy, lust, etc; parts which ANNs do not need to possess in the same way (eg: the fight-or-flight response of the amygdala part of the brain).

[0] https://msail.github.io/post/cnn_human_visual/

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#222

Post by Biganon »

begueradj wrote: post #75

> An individual E. coli has no brain, obviously, and is even many orders of magnitude simpler than a human cell, and yet already it possesses something like a sense of smell, drive, even a memory. A person is billions of billions of more effective cells than an E.coli cell: still our sense of smell, drive and memory do not seem to be billions of billions times more efficient.

Because they don't need to be.

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#223

Post by dekhn »

basil-rash wrote: post #218
dekhn wrote: post #215

Earlier quoted context omitted.

I think I'll stick to the Silmarillion, it's a much more compelling origin story than Genesis (either version).

Feel free. But how much of the world's resources have been dominated by folks placing their faith in Eru Ilúvatar? And I'm sure you're aware Tolkien was a devout Catholic, and described his works as fundamentally Catholic?

Yep, and CS Lewis was religious as well- didn't stop me from enjoying the creation of narnia in the Magician's Nephew. It did stop me from enjoying the Last Battle, as that was too egregious.

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#224

Post by infinite8s »

verisimi wrote: post #182
burnished wrote: post #115

Earlier quoted context omitted.

Yeah I always appreciate that, I hate it when people shy away from honesty because they think some heckler won't understand the subtlety of the observations at play.

You realise of course that models can be wrong. The map is not the terrain. Models are not reality. The observations here are on models. If I knock up something in excel, and other people use that thinking it is how things are, but do not refer to the reality the model represents because there is no way to do that, how useful is the model? Have you ever looked at old medieval beastiaries? Information is being relayed…

All models are wrong, some are just less wrong than others.

For chemotaxis, while they can't observe the underlying processes directly, they result in phenomena that are observable, which can be compared with the same phenomena predicted by simulations and models (the same is true of all scientific fields).

Re: The baffling intelligence of a single cell: The story of E. coli chemotaxis

#225

Post by GirkovArpa »

svnt wrote: post #157
genman wrote: post #125

Earlier quoted context omitted.

No, it is because the probability of arriving to a correct answer increases when there are more members in the group, but only when the individual probability to arrive to a correct conclusion is higher than 50%. Group of smart people is smarter than an individual. The opposite is true too. If the individual probability is less than 50% then the group of people is dumber than the individual.

The answer must also be within all of their domains of expertise for the 50% to have any meaning. You can’t have a “room full of smart people” as you’ll just arrive at suboptimal outcomes because your consensus relies on the lowest common denominator of understanding, which between experts in differing fields can be pretty low.

In the context of Condorcet's jury theorem, the percentages refer to the chance of voting for the correct outcome. Think of a legal trial and there is no ambiguity about the meaning of "50%" is.
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