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Comment by yorwba | Hacker News Reader

The problem with assuming tons of innate knowledge is that it needs to be stored somewhere. DNA certainly contains enough information to determine the development of various different neuron types and which kinds of other neurons they connect to, but it certainly cannot specify weights for every individual synapse, except for animals with very low neuron counts.

So the existence of a sensorimotor feedback loop for a basic behavior is innate (e.g. moving forward to seek food), but the fine-tuning for reliabily executing this behavior while adapting to changing conditions (e.g. moving over difficult terrain with an injured limb after spotting a tasty plant) needs to be learned through interacting with the environment. (Stumbling around eating random stuff to find out what is edible.)

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>certainly cannot specify weights for every individual synapse

That's not the only way to one could encode innate knowledge. Besides, we have demonstrated that animals have innate knowledge experimentally many times, the only reason we can't do this to humans is that it would be horrifically unethical.

>Stumbling around eating random stuff to find out what is edible

Plenty of animals have innate knowledge about what is and isn't edible: it's why, for example, tasty things generally speaking smell good and why things that are bad (rotting meat) smell horrific.

I'm not saying that there's no innate knowledge. This entire list of reflexes https://en.wikipedia.org/wiki/List_of_reflexes is essentially a list of innate knowledge in humans, many of which have been demonstrated in newborns, apparently without considering such experiments unethical.

I'm saying that there are limits to how much knowledge can be inherited. I.e. the question isn't "Where could innate knowledge be encoded other than in synapses?" but "Considering the extremely large number of synapses involved in complex behavior far exceeds genetic storage capacity, how are their weights determined?" And since we know that in addition to having innate behaviors, animals are also capable of learning (e.g. responding to artificial stimuli not found in nature), it stands to reason that most synapse weights must be set by a dynamic learning process.

Yeah but the point was that people are uncomfortable with positing any innate knowledge at all.

> That's not the only way to one could encode innate knowledge.

Maybe sections could be read from DNA and broadcast as action potentials?

There's already ribosomes that go over RNA. You'd need a variant which instead of making amino acids, would read out the base pairs and make something that causes action potentials to happen based on the contents.

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