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Why Is the Human Brain So Efficient? (2018)

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Re: Why Is the Human Brain So Efficient? (2018)

#41

Post by criddell »

The_rationalist wrote: post #23
tegeek wrote: post #15

Earlier quoted context omitted.

Comparing Human Brain with a CPU is misconception. In the past when we didn't have digital computers we used to compare Brain with other machines. And now with a CPU. A Brain from a primitive neuron to higher level is not comparable to any machine at all including the CPU.

Comparing Human Brain with a CPU is misconception. no it is not. Yeah architecturally they are very different and CPU are arguably more programmable / general and less efficient. What does matter is whether CPUs are theoretically able to achieve all the things that a brain can do (and even more) And indeed CPUs as turing complete, programmable machine are a strict superset of what brains can do. The gap between what…

Is there anything analogous to software in biology?

Re: Why Is the Human Brain So Efficient? (2018)

#42

Post by rabryan »

otabdeveloper4 wrote: post #40
The_rationalist wrote: post #23

Earlier quoted context omitted.

Comparing Human Brain with a CPU is misconception. no it is not. Yeah architecturally they are very different and CPU are arguably more programmable / general and less efficient. What does matter is whether CPUs are theoretically able to achieve all the things that a brain can do (and even more) And indeed CPUs as turing complete, programmable machine are a strict superset of what brains can do. The gap between what…

The human brain isn't Turing-complete. Turing completeness implies infinite recursion, which the brain obviously can't do.

Why is that obvious? My brain’s been infinitely recursing for years as far as I know

Re: Why Is the Human Brain So Efficient? (2018)

#43

Post by sooheon »

criddell wrote: post #41
The_rationalist wrote: post #23

Earlier quoted context omitted.

Comparing Human Brain with a CPU is misconception. no it is not. Yeah architecturally they are very different and CPU are arguably more programmable / general and less efficient. What does matter is whether CPUs are theoretically able to achieve all the things that a brain can do (and even more) And indeed CPUs as turing complete, programmable machine are a strict superset of what brains can do. The gap between what…

Is there anything analogous to software in biology?

Biology is the ultimate legacy software running on one of the oldest platforms ever developed, the organic compounds. It is literally a giant genetic algorithm to write instructions (DNA) for manufacturing molecular machines (proteins) that interact with each other in an extremely complex graph of relations (protein pathways, i.e. control flow).

Re: Why Is the Human Brain So Efficient? (2018)

#44

Post by ResidentSleeper »

tegeek wrote: post #15
est31 wrote: post #9

One kind of efficiency which hasn't been talked about is the energy loss of things like state switching and keeping the current state enabled. I think that brains build on much more efficient primitives than the silicon transistors computer chips use and thus can perform far more computations for far less energy than a desktop CPU. Another difference between CPUs and brains is that brains are much less general purpos…

Comparing Human Brain with a CPU is misconception. In the past when we didn't have digital computers we used to compare Brain with other machines. And now with a CPU. A Brain from a primitive neuron to higher level is not comparable to any machine at all including the CPU.

Whether or not it's comparable depends on the level of distinction you're trying to make. Obviously, CPUs don't think or experience the world (but on the other hand that kind of "feature" seems increasingly likely to be implementable in software, even if our current CPU architectures are rather unsuitable for that goal). However, if we're gonna talk about energy efficiency and computation performance, now that it has become evident that the brain is merely a kind of a computer, we can definitely look for parallels.

Re: Why Is the Human Brain So Efficient? (2018)

#45

Post by JoeAltmaier »

LordHeini wrote: post #30

Is it though? I think having a good metric is really hard. For example i can have a neural net running on my smartphone doing recognition tasks. A task the brain is typically good at due to its neural net structure while the computer basically has to simulate the net. But still my smartphone can mark all the faces in a crowd multiple times over in a time i can not recognize even a single person. And that with a camer…

Yes but for integrating information, your brain is marvelous. Somebody in the crown laughs or moves a certain way or you catch a sniff - and BAM you found your person.

Any automated single-skill system might be more efficient, but of course it becomes useless outside its parameters. Put a hat on those people in the crowd and your phone may be totally defeated.

Re: Why Is the Human Brain So Efficient? (2018)

#47

Post by lagadu »

otabdeveloper4 wrote: post #40
The_rationalist wrote: post #23

Earlier quoted context omitted.

Comparing Human Brain with a CPU is misconception. no it is not. Yeah architecturally they are very different and CPU are arguably more programmable / general and less efficient. What does matter is whether CPUs are theoretically able to achieve all the things that a brain can do (and even more) And indeed CPUs as turing complete, programmable machine are a strict superset of what brains can do. The gap between what…

The human brain isn't Turing-complete. Turing completeness implies infinite recursion, which the brain obviously can't do.

Technically Turing completeness requires infinite memory for that (or an infinite tape if we're talking about the original turing machine concept), which no Turing-complete machine has. In other words, the brain is as Turing-complete as any machine that we also consider to be so. We'll always be bounded by limited memory and limited time.

Re: Why Is the Human Brain So Efficient? (2018)

#48

Post by SomeoneFromCA »

The_rationalist wrote: post #23
tegeek wrote: post #15

Earlier quoted context omitted.

Comparing Human Brain with a CPU is misconception. In the past when we didn't have digital computers we used to compare Brain with other machines. And now with a CPU. A Brain from a primitive neuron to higher level is not comparable to any machine at all including the CPU.

Comparing Human Brain with a CPU is misconception. no it is not. Yeah architecturally they are very different and CPU are arguably more programmable / general and less efficient. What does matter is whether CPUs are theoretically able to achieve all the things that a brain can do (and even more) And indeed CPUs as turing complete, programmable machine are a strict superset of what brains can do. The gap between what…

> What does matter is whether CPUs are theoretically able to achieve all the things that a brain can do (and even more) And indeed CPUs as turing complete, programmable machine are a strict superset of what brains can do.

It is not proven in any way. Turing's postulate is just a postulate, it is not even a theorem, just a conjecture. And AFAIK it cannot be proven, actually.

Re: Why Is the Human Brain So Efficient? (2018)

#49

Post by coreyp_1 »

The_rationalist wrote: post #23
tegeek wrote: post #15

Earlier quoted context omitted.

Comparing Human Brain with a CPU is misconception. In the past when we didn't have digital computers we used to compare Brain with other machines. And now with a CPU. A Brain from a primitive neuron to higher level is not comparable to any machine at all including the CPU.

Comparing Human Brain with a CPU is misconception. no it is not. Yeah architecturally they are very different and CPU are arguably more programmable / general and less efficient. What does matter is whether CPUs are theoretically able to achieve all the things that a brain can do (and even more) And indeed CPUs as turing complete, programmable machine are a strict superset of what brains can do. The gap between what…

"And indeed CPUs as turing complete, programmable machine are a strict superset of what brains can do."

This is a fundamental assertion that I do not believe you can make.

The brain cannot simulate a turing machine. It does not have infinite memory, which is a requirement for a turing machine. It can, however, stimulate a linearly bounded automata.

It is also not implicitly obvious that a turing machine can simulate a brain. The primary difficulty that I do not yet see a way around is the fact that a turing machine, which has as its control unit a finite State machine, is bound by the finiteness of those states (finiteness of representation, not of number). The brain has no such constraint. It is analog, and therefore infinite in State representation.

In my opinion, this is more akin to the P versus NP problem, and that we know what needs to be equivalent in order to say that P equals NP, but no one has proved it or disproved it yet. That's how I feel about the statement about Turing machines and the brain. I do not believe we can be dogmatic on that aspect yet either way. We may have opinions, just as we may have opinions about P vs NP, but we must also be careful about stating what is provable and what is opinion, and that is all I'm trying to do.

Of course, I am willing and very interested to gain more insight in this area, so discussion is welcome!

Re: Why Is the Human Brain So Efficient? (2018)

#50

Post by jayjader »

gambiting wrote: post #37
papito wrote: post #33

Earlier quoted context omitted.

Neural networks also have no ability to create new information based on their own mistakes. What is a mistake? When does something look "off" but still very interesting? For example, you can feed a neural net all the recipes of burgers to create a perfect burger. Great. But how does the same net invent the burger? The burger, like many foods or accidental art, was invented as a result of scarcity, circumstance, exper…

>>For example, you can feed a neural net all the recipes of burgers to create a perfect burger. Great. But how does the same net invent the burger? Wait....but it just....did? It took the information about all possible burger recipes and invented a new one out of these. Like, a human could only invent a new burger if they knew anything about burgers in the first place, at the very least that it's a bun with some fill…

Not OP, but I think they're not talking about inventing a _new_ burger, but inventing _the_ burger, as in the first one ever.

As in, the neural net in this example is able to improvise a new burger recipe solely because it was given existing recipes to burgers as input; it did not come up with the notion of a burger and then produce a recipe that outputs something fulfilling that notion when followed.

Personally, I would argue that this distinction is not as clear-cut as the tone of the original comment seems to suggest. Humans didn't invent the burger from nothing either. We've been grilling meat and making bread for millennia, and sandwiches have been a thing for over a century.

A 'burger' is just another iteration of our biological neural nets' attempts to make food from ingredients already present in our physical reality. Given that we flow in a single direction through time, any food we make is in turn added to our list of ingredients for making food "the next time". One could argue it is only a matter of time once meat can be ground into patties and grains turned into bread that burgers start being made - given the relative benefits humans gain from consuming both.

This comes back to what others have expressed elsewhere in this thread, that the probable [most] important distinctions aren't between software vs hardware, or organic life vs silicon processors, but the environment & capacity to interact with said environment. Some sense of "innate tendency to experiment" (i.e. curiosity) is probably either equal in importance or a direct runner-up.

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