4 ms·

> Any task of human cognition that the sack of meat in a skull can do, a digital algorithm will be able to do, because the former is just slow, slow analog meat

> Any task of human cognition that the sack of meat in a skull can do, a digital algorithm will be able to do, because the former is just slow, slow analog meat. It's not slow at all. And you are obsessed with meat.

sharemywin 9y ago
All this talk of meat is making me hungry...stupid auto correct.... :<
- rapnie 9y ago
  Ah.. brings me to another invention: artificial meat, but as tasty and indiscernable as the real thing, without all the food waste required to raise cattle. Currently still in the lab phase, I think.
logicallee 9y ago
It's exceedingly slow. Neurons fire at not 4 gigahertz, 400 megahertz, 40 megahertz, 4 megahertz, 400 kilohertz, 40 kilohertz, 4 kilohertz, or 0.4 kilohertz (400 hertz.) They fire at < 1 hertz to about 200 hertz. [1] That is literally 8 orders of magnitude slower than processers. 8 orders of magnitude is the size of difference between a grain of sand and 1.2 short tons. In the time that your neuron moves 1 grain of sand, a computer can move 1.2 short tons worth of sand 1 grain at a time (talking about just cache here) - because it's switching at 4 GHz instead of 10 hertz. That is enough to make a lot of back and forth trips. Now, you have to make a lot of these back and forth trips because the brain is extremely parallel. But the difference between these extremely slow biochemical firing speeds and gigahertz light speed enables this. The speed of propagation in the brain is about 100 meters/second [2]. The speed of propagation between two fiber optic end-points is about 299 792 458 meters/second. That gives you 7 orders of magnitude to play with. Or, in other words, it can let you take seven orders of magnitude more trips across a data center (or go that much farther) before you miss a real-time deadline for when you need to address a neuron by. In the future it's pretty clear that computers are not going to think as fast as the human brain when doing similar calculations using a similar topology, but, for example, 10,000 times faster than real-time. This really shouldn't surprise anyone growing up in technology. Brains are slow, mechanical devices. They're not digital and they don't do signal processing at the speed of light. It's taken us some time to catch up because a hundred billion neurons is still a lot of neurons, and algorithm development using similar topologies has been slow. [1] https://aiimpacts.org/rate-of-neuron-firing/#Estimates_of_rate_of_firing_in_humanneocortex https://aiimpacts.org/rate-of-neuron-firing/#Estimates_of_ra... [2] https://hypertextbook.com/facts/2002/DavidParizh.shtml https://hypertextbook.com/facts/2002/DavidParizh.shtml
- babygoat 9y ago
  Are brains working on the bit level? All that aside, how does general cognition emerge from speed? Why hasn't anyone made a "slow" version yet?
  - logicallee 9y ago
    No, brains work on the neuron level. We know how many neurons there are (about 100b). The reason I mention the bit level is because if we knew for a fact that the "code" that ran the structure of the brain fit in, say, 64 KB (if we knew this because the whole human genome fit in 64 KB) we would have long-since tried to emulate it. Instead it is "guaranteed" (in a sense) to be a subset of about 700 MB of bits. That's the human source code. It just gives you a sense of the scale of complexity that might be involved there. (700 MB is quite a lot of source code, don't get me wrong.)

sharemywin 9y ago

All this talk of meat is making me hungry...stupid auto correct.... :<

rapnie 9y ago
Ah.. brings me to another invention: artificial meat, but as tasty and indiscernable as the real thing, without all the food waste required to raise cattle. Currently still in the lab phase, I think.

logicallee 9y ago

It's exceedingly slow. Neurons fire at not 4 gigahertz, 400 megahertz, 40 megahertz, 4 megahertz, 400 kilohertz, 40 kilohertz, 4 kilohertz, or 0.4 kilohertz (400 hertz.) They fire at < 1 hertz to about 200 hertz. [1] That is literally 8 orders of magnitude slower than processers. 8 orders of magnitude is the size of difference between a grain of sand and 1.2 short tons. In the time that your neuron moves 1 grain of sand, a computer can move 1.2 short tons worth of sand 1 grain at a time (talking about just cache here) - because it's switching at 4 GHz instead of 10 hertz. That is enough to make a lot of back and forth trips. Now, you have to make a lot of these back and forth trips because the brain is extremely parallel. But the difference between these extremely slow biochemical firing speeds and gigahertz light speed enables this. The speed of propagation in the brain is about 100 meters/second [2]. The speed of propagation between two fiber optic end-points is about 299 792 458 meters/second. That gives you 7 orders of magnitude to play with. Or, in other words, it can let you take seven orders of magnitude more trips across a data center (or go that much farther) before you miss a real-time deadline for when you need to address a neuron by. In the future it's pretty clear that computers are not going to think as fast as the human brain when doing similar calculations using a similar topology, but, for example, 10,000 times faster than real-time. This really shouldn't surprise anyone growing up in technology. Brains are slow, mechanical devices. They're not digital and they don't do signal processing at the speed of light. It's taken us some time to catch up because a hundred billion neurons is still a lot of neurons, and algorithm development using similar topologies has been slow. [1] https://aiimpacts.org/rate-of-neuron-firing/#Estimates_of_rate_of_firing_in_humanneocortex https://aiimpacts.org/rate-of-neuron-firing/#Estimates_of_ra... [2] https://hypertextbook.com/facts/2002/DavidParizh.shtml https://hypertextbook.com/facts/2002/DavidParizh.shtml

babygoat 9y ago
Are brains working on the bit level? All that aside, how does general cognition emerge from speed? Why hasn't anyone made a "slow" version yet?
- logicallee 9y ago
  No, brains work on the neuron level. We know how many neurons there are (about 100b). The reason I mention the bit level is because if we knew for a fact that the "code" that ran the structure of the brain fit in, say, 64 KB (if we knew this because the whole human genome fit in 64 KB) we would have long-since tried to emulate it. Instead it is "guaranteed" (in a sense) to be a subset of about 700 MB of bits. That's the human source code. It just gives you a sense of the scale of complexity that might be involved there. (700 MB is quite a lot of source code, don't get me wrong.)